if

1. conjunction /ɪf/

a) Supposing that, assuming that, in the circumstances that;

If it rains, I will get wet.

b) Supposing that;

Id prefer it if you took your shoes off.

2. noun /ɪf/

An uncertainty, possibility, condition, doubt etc.

Sir Fran. Nay, but Chargy, if——— ¶ Miran. Nay, Gardy, no Ifs.——Have I refusd three northern lords, two British peers, and half a score knights, to have put in your Ifs?