Productive prefix attached to nouns, often loanwords, to mean 'before' or 'preliminary'. Common in compounds like プレテスト (pre-test) or プレオープン (pre-opening).
A pre-launch event for the new product was held.
Check the team's condition in pre-season games.
The pre-sale starts next week.
ポスト is the matching loanword prefix meaning 'post-/after', the opposite of プレ meaning 'pre-/before'.
preview
premium price; scalper price; marked-up price
premium account
pre-cut; prefabricated
presale; advance sale
pre-opening; soft opening; preview event
precast
preprint
prerelease
Borrowed from English 'pre-', used as a prefix in Japanese mainly with loanwords.
pre-printed forms
pre-babyboomers