1. Supposing that; in case that.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• af,
• sf,
• gf,
• ifwe,
• inf,
• ife,
• ift,
• wf,
• bf,
• if,
• jf,
• ifi,
• asif,
• tf,
• soif,
• ifel,
• jify,
• tif,
• ifyo,
• wif

• in-,
• Im-,
• F,
• iffy,
• is,
• i,
• I'm,
• ID,
• ia,
• il,
• i'd,
• iv,
• Il-,
• i's,
• -ic,
• It,
• Of,
• in.

The plural of the "If" can be the "ifs".

The singular of the "If" can be the "If".