Tentacular tubular process of most echinoderms (starfish and sea urchins and holothurians) having a sucker at the end and used for e.g. locomotion and respiration WordNet 3.0 & Open English WordNet

Tube feet are small active tubular projections on the oral face of an echinoderm, whether the arms of a starfish, or the undersides of sea urchins, sand dollars and sea cucumbers; they are more discreet though present on brittle stars, and have only a feeding function in feather stars. Wikipedia

Small multipurpose appendages in echinoderms Wikipedia Disambiguation

Multipurpose organs of echinoderms Wikidata

A locomotor appendage of an echinoderm consisting of a tube with longitudinal muscles, pressurized by water. Wiktionary