leg up noun 3verb 1forms 5 noun3 •The act of assisting another's progress over a wall or other obstacle by forming a step for one of their feet with one's hands. •(figurative) Assistance, help given to get started or overcome a problem or obstacle. •(figurative) A boost, a sudden improvement; an advantage, an edge. verb1 •To walk a horse on a hard surface regularly. formslegged up · legging up · legs up · leg ups · leg-ups