an indentation, a dip or divot, a hollow, a dent in a surface

a sunken center / a place or object with a sunken center

an area with sides higher than the center: an indentation, a depression, a dip, a divot, a hole / (slang) female genitalia, the vagina

Short for ボール紙 (bōru-gami): non-corrugated cardboard, pasteboard / Short for 段ボール (danbōru): corrugated cardboard

ball (formal dance event)

Clipping of 航空母艦 (kōkū bokan, “aircraft carrier”).

dolmen - a prehistoric megalithic tomb consisting of a capstone supported by two or more upright stones, most having originally been covered with earth or smaller stones to form a barrow.

a mother ship, a tender (watercraft) / Short for 航空母艦 (kōkū bokan, “aircraft carrier”).

Bovril

volcano