the.com/vocabulary

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means The whole stock of words a person knows or uses, or the set of words belonging to a particular language, subject, or activity.

from From the Latin vocabulum, "a name, a designation," itself rooted in vocare, "to call" (a cousin of "voice" and "vocal"). Latin vocabularium meant a list of words, and the term arrived in English through that scholarly channel in the 1500s, first as a word-list and only later as the inner hoard each speaker carries.

average adult
Knows around 20,000 to 35,000 words.
acquisition rate
Children learn roughly one new word per waking hour.
recognition gap
You understand far more words than you ever speak.
oldest word
"Mother" traces back tens of thousands of years.
Shakespeare
Coined or popularized over 1,700 words still used.
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