something having a flat or level surface, platform, etc.; specif.,
- Slang an aircraft carrier
- a style of man's haircut in which the hair on top of the head is cropped so that it bristles up to form a flat surface
- An aircraft carrier.
- A short haircut in which the hair is brushed straight up and cropped flat across the top.
- An acoustic guitar having a flat piece of wood on the side where the strings are, a single sound hole in the center of the body, and a bridge attached just below the sound hole.
- (US) A short haircut in which the hair is brushed straight up then cut flat across the top
- (US, informal) An aircraft carrier; origin credited since 1942 to a laconic message, “Scratch one flattop,” radioed by LCDR Robert E. Dixon to USS Lexington, whose commanding officer credited the pilot with coining the standard USN slang; see Wikipedia for Battle of Coral Sea
- Abbreviated form of flattop grill.