if Definition

if
conj

1. In the event that; on condition that; supposing that.

Example: I'll go if he asks me to
2. Although; even though.

Example: It was very enjoyable, if overpriced
3. Whenever.

Example: She jumps if the phone rings
4. Whether.

Example: I wonder if he knows
5. Used to express a wish

Example: If only it would stop raining!
Form: if only (usually)
6. Used to make a polite request or suggestion.

Example: if you wouldn't mind stopping just a minute
7. Used in exclamations, to express surprise or annoyance

Example: Well, if it isn't that book I'd thought I'd lost!

noun

1. A condition or supposition.

Example: too many ifs and buts
2. An uncertainty.

Idiom: if anything

Perhaps; on the contrary.

Idiom: if only

See sense 5 above.

Idiom: if only to do something

If for no other reason than to do it.
Example: I'll be there, if only to give her moral support

Idiom: if you like

To say it another way.

If you want or approve.

Etymology: Anglo-Saxon gif.