noun: (especially in the compound "flehmen response") Flaring of the lip in mammals, associated with intensive smelling; flehming.
verb: Alternative form of flehm [(intransitive) To exhibit the flehmen response, i.e., to draw back the lips, allowing scent to reach the Jacobson’s organ, an auxiliary olfactory organ found in many animals.]
noun: Nonstandard form of flehmen. [(especially in the compound "flehmen response") Flaring of the lip in mammals, associated with intensive smelling; flehming.]