big, large, great

凹む: dent; sink in; be defeated

dent, hollow

a revolving door

a pit, a hollow, a cavity, a depression, a dent / a mistake, and error / a moment of weakness or confusion, being at a loss

to become hollow, cave in, sink in: see the kubomu reading above / to decline below a certain point, to become less / to be stuck to be at a loss: see 困る (komaru). / to yield, to submit

Western-style door

車: car; wheel

swing door

platform door; platform screen door