Definition - A terminal combining form that is commonly used in linguistics (1) to indicate a social or regional variety (e.g. idiolect) and (2) to form linguistic technical terms (e.g. acrolect).

Etymology -
It derives from the word dialect.

Oxford English Dictionary -
The combining form's first citation is from 1965:
"I will refer to this topmost dialect in the local sociolinguistic hierarchy as acrolect (from acro- ‘apex’ plus -lect as in dialect). …."
(W. A. Stewart in R. W. Shuy Social Dial. & Lang. Learning 15)

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