a light sandal, typically of plastic or rubber, with a thong between the big and second toe

a backward handspring

a switching circuit which works by changing from one stable state to another, or through an unstable state back to its stable state, in response to a triggering pulse

move with a flapping sound or motion

she flip-flopped off the porch in battered trainers

make an abrupt reversal of policy

the candidate flip-flopped on a number of issues