Whiskers on a cat
A whisker was a type of hair present on animals that was capable of sensory determination. The term "whiskers" could also collquially apply to a Human's beard. (TNG: "A Fistful of Datas")
Talaxians had whiskers. In 2374, Neelix fantasized about a Mari woman tugging on them. (VOY: "Random Thoughts")
In 2267 and 2269, the White Rabbit invoked his whiskers when proclaiming his own tardiness. (TOS: "Shore Leave",TAS: "Once Upon a Planet")