ace
Literally, yes. Figuratively, to most people, no. The term 'four letter word' normally refers to four letter curse words.
adjustment?
bathers (Australian term for swimsuit)
acronym
literal
The African Luhya term for the English word "letter" is 'ibarua'.
ace
The term pi comes from the greek letter pi, which is the first letter of the word which in English is "perimeter".
obsolesce
Contraction.
term
abed
in geometry, width
In re
The mean is the average value.
Aft. A boating term.