You use flaccid to describe a part of someone's body when it is unpleasantly soft and not hard or firm. I picked up her wrist. It was limp and flaccid. = limp. soft and weak instead of firm (flaccidus, from flaccus )
lacking in strength or firmness or resilience; "flaccid muscles"; "took his lax hand in hers"; "gave a limp handshake"; "a limp gesture as if waving away all desire to know"