If you've been reading about AAC or talking with a speech-language pathologist, you've probably heard the terms "core words" and "fringe words." These two categories describe different types of vocabulary, and understanding the difference between them is one of the most practical things you can learn as a parent, teacher, or therapist supporting someone who uses AAC.
This guide breaks down what core words and fringe words are, how they compare, and how to use both effectively.
What Are Core Words?
Core words are a small set of high-frequency words that people use constantly in everyday conversation. They show up in every topic, every setting, and every age group. Linguists sometimes call them "function words" because they serve as the building blocks of sentences.
Characteristics of core words
- High frequency. A small set of a few hundred core words makes up the vast majority of everything we say.
- Flexible across contexts. The word "go" works at the park, at school, at dinner, and at bedtime. It doesn't depend on a specific topic.
- Mostly not nouns. Core words tend to be verbs, pronouns, adjectives, prepositions, and determiners.
- Stable over time. The same core words appear in toddler speech, teen conversations, and adult language.
- Harder to picture. Words like "more," "not," and "it" are abstract, which makes them trickier to represent with symbols but more powerful for communication.
Examples of core words
| Category | Examples |
|---|---|
| Pronouns | I, you, it, my, that, this |
| Verbs | want, go, get, put, make, help, like, see, look |
| Adjectives | more, big, little, good, different, same |
| Prepositions | in, on, up, off, out, with |
| Negation | no, not, don't |
| Social words | hi, bye, please, thank you, yes |
| Determiners | the, a, some, all |
What Are Fringe Words?
Fringe words (also called "fringe vocabulary" or "extended vocabulary") are topic-specific words that carry concrete meaning. They tend to be the nouns and proper nouns that name specific people, places, things, and ideas.
Characteristics of fringe words
- Lower frequency. Each individual fringe word appears far less often in conversation than a core word does.
- Context-dependent. "Dinosaur" matters a lot during a museum trip but rarely comes up at dinner.
- Mostly nouns. Fringe vocabulary is dominated by nouns, though it also includes specialized verbs and adjectives.
- Highly personal. The fringe words your child needs depend on their interests, their environment, and the people in their life. One child might need "Minecraft" and "trampoline" while another needs "horses" and "ballet."
- Easy to picture. Because fringe words name concrete things, they're often easier to represent with images and symbols.
Examples of fringe words
| Category | Examples |
|---|---|
| Food | cookie, apple, juice, pizza, milk |
| Animals | dog, cat, fish, dinosaur, horse |
| People | mom, dad, grandma, teacher, friend's name |
| Places | school, park, store, home, playground |
| Toys/activities | ball, blocks, iPad, swing, bike |
| Clothing | shoes, hat, jacket, socks |
Core Words vs Fringe Words: Side-by-Side Comparison
| Dimension | Core Words | Fringe Words |
|---|---|---|
| Frequency | Very high (majority of daily speech) | Lower (minority of daily speech) |
| Flexibility | Work across all topics and settings | Tied to specific topics or contexts |
| Word types | Verbs, pronouns, adjectives, prepositions | Mostly nouns and proper nouns |
| Number needed | 200 to 400 words cover most communication | Thousands of words, constantly growing |
| Abstractness | Often abstract ("more," "not," "that") | Usually concrete ("cookie," "dog," "park") |
| Symbol representation | Harder to represent with pictures | Easier to represent with pictures |
| Sentence building | Form the structure of sentences | Fill in the specific content |
| Personalization | Same for everyone | Unique to each person's life |
| Teaching approach | Model across many contexts throughout the day | Teach in relevant moments and activities |
How Core and Fringe Words Work Together
Here's the key insight: core words and fringe words aren't competing categories. They're partners. Every meaningful sentence combines both types.
Consider these examples:
- "I want cookie" = 2 core words (I, want) + 1 fringe word (cookie)
- "Go to park" = 2 core words (go, to) + 1 fringe word (park)
- "Not that one, the big dinosaur" = 5 core words (not, that, one, the, big) + 1 fringe word (dinosaur)
- "Put shoes on" = 2 core words (put, on) + 1 fringe word (shoes)
- "I don't like it" = 4 core words (I, don't, like, it) + 0 fringe words
Notice the pattern? Core words appear in almost every sentence, providing the grammatical glue. Fringe words drop in occasionally to specify the topic. You need both, but if you had to prioritize, core words give you far more communicative power per word learned.
That's also why a child who learns 20 core words can build hundreds of different sentences. A child who learns 20 fringe nouns can label 20 things but can't yet ask for them, refuse them, describe them, or talk about them in any flexible way.
The 80/20 Pattern
Research consistently shows that a relatively small number of core words accounts for the vast majority of what people say. This pattern holds across ages, languages, and communication contexts.
Yorkston and colleagues (1988) conducted early word-frequency analyses that demonstrated how a small set of words dominated adult speech samples. Their work helped establish the concept that frequency-based vocabulary selection could make AAC systems far more efficient.
Banajee, DiCarlo, and Stricklin (2003) studied toddlers aged 2 to 3 in daycare settings. They found that roughly 250 words accounted for the vast majority of the children's communication. Most of these high-frequency words were core vocabulary, not the object labels that many early AAC systems emphasized.
Baker, Hill, and Devylder (2000) analyzed vocabulary use across multiple environments and found that core words remained consistent regardless of where communication happened. Whether at home, school, or in the community, the same core words kept appearing.
More recently, Binger, Magallanes, San Miguel, Harrington, and Hahs-Vaughn (2024) published a study in the American Journal of Speech-Language Pathology examining how toddlers combine core and fringe words in their natural utterances. Their findings reinforced that even very young children rely heavily on core words to build multi-word combinations, and that fringe words serve as the content anchors within those combinations.
The practical takeaway? If you're setting up an AAC system and wondering what vocabulary to prioritize, core words give you the most communicative bang for your effort. But fringe words are what make communication personal and relevant.
For a deeper dive into the research, see our post on why core words matter more than nouns in AAC.
Practical Tips for Balancing Core and Fringe Words
Knowing the difference between core and fringe words is helpful. Knowing how to teach and support both is where it gets practical. Here are some strategies that work.
1. Start with core words, then layer in fringe
When introducing AAC, begin with a set of high-frequency core words that your child can use across situations. Words like "want," "more," "stop," "go," "help," and "not" are useful in almost every interaction. Once those are becoming familiar, start adding fringe words that matter to your child's daily life.
If you're wondering where to start, check out our guide on core words to teach first.
2. Model both types throughout the day
Modeling means using the AAC system yourself to show your child how it works. When you model, naturally use both core and fringe words. During snack time, you might model "I want crackers" (core + fringe) or "more juice please" (core + fringe + core). The goal is to show how core words combine with fringe words to create real communication.
3. Customize fringe vocabulary for activities
Before a specific activity, make sure the relevant fringe words are available. Going to the park? Make sure "swing," "slide," and "sand" are accessible. Mealtimes need food names. School activities need classroom vocabulary. Core words stay the same across all of these situations, but fringe words change.
4. Don't overload the system with nouns
One common mistake in AAC setup is filling the device with hundreds of nouns while providing few verbs, adjectives, or other core words. A child with 200 food labels but no way to say "want," "don't like," or "more" can only point to pictures of food. They can't make requests, express preferences, or have conversations about food. Balance matters.
5. Follow your child's interests for fringe words
The best fringe words to add are the ones your child actually cares about. If they love trains, add train-related fringe words. If they're into a specific TV show, add character names. Motivation drives learning, and having personally meaningful fringe words on the device gives your child a reason to explore and use it.
6. Revisit and update fringe words regularly
Core words are stable. You'll teach the same core words for years. Fringe words, on the other hand, need updating. Your child's interests change, new topics come up at school, seasons shift, and the family might get a new pet. Check in regularly to make sure the fringe vocabulary on your child's device still reflects their current life.
Putting It All Together
The distinction between core words and fringe words isn't just academic. It has direct implications for how you set up an AAC system, what words you teach first, and how you model language throughout the day.
Core words are the engine of communication. They're small in number, massive in impact, and they work everywhere. Fringe words are the color and detail. They make communication personal, specific, and engaging.
The best AAC systems and the most effective communication partners provide both. Prioritize core words for their flexibility, customize fringe words for relevance, and model how the two types combine to build real sentences.
Your child doesn't need to choose between core and fringe vocabulary. They need both, working together.
References
- Baker, B., Hill, K., & Devylder, R. (2000). Core vocabulary is the same across environments. Proceedings of the CSUN Technology and Persons with Disabilities Conference.
- Banajee, M., DiCarlo, C., & Stricklin, S. B. (2003). Core vocabulary determination for toddlers. Augmentative and Alternative Communication, 19(2), 67-73.
- Binger, C., Magallanes, S., San Miguel, M., Harrington, R., & Hahs-Vaughn, D. (2024). Core and fringe word use in the natural language of toddlers. American Journal of Speech-Language Pathology, 33(3), 1252-1267.
- Yorkston, K. M., Dowden, P. A., Honsinger, M. J., Marriner, N., & Smith, K. (1988). A comparison of standard and user vocabulary lists. Augmentative and Alternative Communication, 4(4), 189-210.