noun

A surprise attack by people lying in wait in a concealed position.

seven members of a patrol were killed in an ambush

surprise attack,trap,snare,pitfall,lure

transitive verb

Make a surprise attack on (someone) from a concealed position.

they were ambushed and taken prisoner by the enemy

attack by surprise,trap,surprise,pounce on,lay a trap for,set an ambush for,lie in wait for,waylay,entrap,ensnare