1. Introduces a conditional clause
   "I will go to university if I can afford it" 
2. Despite being
   "he's nice, if rather patronizing" 
3. Every time that
   "if I call you are always engaged"
   - whenever, when

Encyclopedia: If

• underexposure
• underfed
• underfeed
• underfelt
• underfoot
• underframe
• underfur
• undergarment
• undergird
• underglaze
• undergo
• undergrad
• undergraduate
• underground
• underground press
• Underground Railroad
• Underground Railway
• undergrow
• undergrowth
• underhand
• underhanded
• underhandedly
• underhung
• underivative
• underived