iff /if/ (logic)

Used to express if and only if

• sheet lightning
• sheet metal
• sheet music
• sheet rubber
• sheets
• sheet tin
• sheet to the wind
• sheety
• SHEFC
• Sheffield plate
• shehita
• shehitah
• shehitahs
• shehitas
• sheik
• sheikdom
• sheikdoms
• sheikh
• sheikha
• sheikhas
• sheikhdom
• sheikhdoms
• sheikhs
• sheiks
• sheila