Definition of "IF"

IF

noun
countable and uncountable, plural IFs
1. Initialism of interactive fiction.
  Quotations
  The “Zarfian Cruelty Scale” rates games as Merciful, Polite, Tough, Nasty, or Cruel. The scale describes how works of IF become unwinnable, especially how and when the interactor (here a player, and one trying to win) learns this.
  2007, Jeremy Douglass, Command Lines, page 88
2. Initialism of impact factor.
3. (biochemistry) Initialism of intermediate filament.
4. (electronics) Initialism of intermediate frequency.
5. (nutrition) Initialism of intermittent fasting.