1. A thoracic appendage of a barnacle or other cirripede crustacean, modified as a filtering or food-collecting organ.

2. A tiny mouth tentacle of a lancelet (see cephalochordata).

3. Any of various slender appendages of annelid worms.

4. A bundle of cilia that serves as a locomotory organ in certain ciliate protists (see ciliophora), such as Stylonychia.

5. A spiny or whiplike tip of a leaf.