The definition of lexical is something that relates to vocabulary or the words which make up a language.(adjective)
An example of lexical used as an adjective is the phrase lexical similarity which means words that appear to be similar to other words.
See lexical in Webster's New World College Dictionary
Origin: ModL lexicalis < Gr lexikon, lexicon
See lexical in American Heritage Dictionary 4
Origin: + -al1.
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