euglenoidPronunciation: /juːˈgliːnɔɪd/ BiologyDefinition of euglenoid noun a flagellated single-celled organism of a group that comprises euglena and its relatives. Division (or phylum) Euglenophyta adjective relating to euglenoids. (of cell locomotion) achieved by peristaltic waves that pass along the cell, characteristic of the euglenoids. euglenoid in other Oxford dictionaries Definition of euglenoid in the US English dictionary