(noun)
a basic attacking move involving a quick forward thrust made with one's arm or more commonly, with a weapon;
e.g. The boxer made a lunge at her opponent.
(noun)
an exercise or stretch in which a person steps forward or sideways from a standing position such that their front knee is bent which their upper body stays straight;
e.g. He did a lunge with each leg to stretch his muscles.
(verb)
to quickly and suddenly move forward, or to make a forward thrust with a weapon or a part of one's body, typically in order to attack someone/something;
e.g. They were taught to lunge forward as an offensive technique in fencing class.
(verb)
to perform an exercise or stretch by stepping forward or sideways from a standing position such that one's front knee is bent and one's upper body is straight;
e.g. I started to lunge in order to warm up my leg muscles before the race.