One on the lam is an idiom that refers to someone who is running away or hiding from the law. The term is derived from the phrase 'on the lam, ' which means to be in flight. The crossword solutions for this term are FLEER (5 letters) and ESCAPEE (7 letters). FLEER is a verb meaning to turn and run away in fear or to mock or jeer at someone. ESCAPEE is a noun referring to a person who has escaped from confinement or captivity.