- 1: a list or collection of words or of words and phrases usually alphabetically arranged and explained or defined : lexicon
- 2a : a sum or stock of words employed by a language, group, individual, or work or in a field of knowledge
- b : a list or collection of terms or codes available for use (as in an indexing system)
A person's vocabulary is the set of words they are familiar with in a language. A vocabulary usually grows and evolves with age, and serves as a useful and fundamental tool for communication and acquiring knowledge.
Knowing and using a word
A vocabulary is defined as "all the words known and used by a particular person". However, the words known and used by a particular person do not constitute all the words a person is exposed to. By definition, a vocabulary includes the last two categories of this list:
- 1. Never encountered the word.
- 2. Heard the word, but cannot define it.
- 3. Recognize the word due to context or tone of voice.
- 4. Able to use the word but cannot clearly explain it.
- 5. Fluent with the word – its use and definition.
Types of vocabulary
Listed in order of most ample to most limited:
- Reading vocabulary
- Listening vocabulary
- Writing vocabulary
- Speaking vocabulary
A person's speaking vocabulary is all the words he or she can use in speech. Due to the spontaneous nature of the speaking vocabulary, words are often misused. This misuse – though slight and unintentional – may be compensated by facial expressions, tone of voice, or hand gestures.
"Focal vocabulary" is a specialized set of terms and distinctions that is particularly important to a certain group; those with a particular focus of experience or activity. A lexicon, or vocabulary, is a language's dictionary, its set of names for things, events, and ideas. Some linguists believe that lexicon influences people's perception on things, the Sapir–Whorf hypothesis. For example, the Nuer of Sudan have an elaborate vocabulary to describe cattle. The Nuer have dozens of names for cattle because of the cattle's particular histories, economies, and environments. This kind of comparison has elicited some linguistic controversy, as with the number of "Eskimo words for snow". English speakers can also elaborate their snow and cattle vocabularies when the need arises.
Initially, in the infancy phase, vocabulary growth requires no effort. Infants hear words and mimic them, eventually associating them with objects and actions. This is the listening vocabulary. The speaking vocabulary follows, as a child's thoughts become more reliant on its ability to express itself without gestures and mere sounds. Once the reading and writing vocabularies are attained – through questions and education – the anomalies and irregularities of language can be discovered.
In first grade, an advantaged student (i.e. a literate student) knows about twice as many words as a disadvantaged student. Generally, this gap does not tighten. This translates into a wide range of vocabulary size by age five or six, at which time an English-speaking child will know about 2,500–5,000 words. An average student learns some 3,000 words per year, or approximately eight words per day.
After leaving school, vocabulary growth reaches a plateau. People may then expand their vocabularies by engaging in activities such as reading, playing word games, and participating in vocabulary programs.