What is the X in X-mas?
1650s (as exhibiter, 1590s), from Late Latin exhibitor, agent noun from past participle stem of Latin exhibere (see exhibition).
mid-15c., from Latin exhibitus, past participle of exhibere "to hold out, display, show, present, deliver" (see exhibition). Related: Exhibited; exhibiting.
1620s, "document or object produced as evidence in court," from Latin exhibitum, neuter past participle of exhibere (see exhibition). Meaning "object displayed in a fair, museum, etc." is from 1862. Transferred use of exhibit A "important piece of evidence" is by 1906.