1. Causing formation of comedones

Encyclopedia: Comedogenic

• knock over
• knock rummy
• knock-down-and-drag-out
• knock-knee
• knock-kneed
• knock-on effect
• knock-up
• knockabout
• knockdown
• knockdown-dragout
• knocked out
• knocker
• knocking
• knockoff
• knockout
• knockout drops
• knockout punch
• knockwurst
• knoll
• knop
• Knossos
• knot
• knotgrass
• knothole
• knotted