1. Of which person?
   "whose is this coat?" 
2. Of whom, of which
   "a barn whose red planks have weathered to dark brown"

Sounds like: who's

Encyclopedia: Whose

• double-bitted axe
• double-blind experiment
• double-blind procedure
• double-blind study
• double-bogey
• double-breasted
• double-breasted jacket
• double-breasted suit
• double-check
• double-chinned
• double-click
• double-crosser
• double-crossing
• double-dealer
• double-dealing
• double-decker
• double-dip
• double-dyed
• double-edged
• double-entry bookkeeping
• double-faced
• double-geared
• double-glaze
• double-humped
• double-hung window