The most common and most likely answer to this crossword clue is the 5 letter word LEXIS
L
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X
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S
More clues leading to the result LEXIS
Buddy explains!

The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does LEXIS mean?
LEXIS noun- The set of all words and phrases in a language; any unified subset of words from a particular language.
- (pedagogy, TEFL) Words, collocations, and common phrases in a language; vocabulary and word combinations.
- The vocabulary used by a writer