flex off noun 1verb 1forms 4 noun1 •(informal) A competitive or friendly showdown where competitors voluntarily contract, isolate, and display their muscles to showcase their definition, size, and symmetry. verb1 •(US) To take time off from work using a flexible time-off policy, generally allowing time off at will instead of using accrued sick or vacation time. formsflexed off · flexing off · flexes off · flex offs