Adapted for sucking; functioning as a sucker or sucking-organ of any kind: sucking: haustellate: as, the suctorial mouth of a lamprey, the suctorial tongue (antlia) of a butterfly or moth; the suctorial proboscis of a flea; the suctorial disk of a sucking-fish, an octopod, a leech; the suctorial facets of a trematoid worm; the suctorial tentacles of an infusorian.Capable of sucking; fitted for imbibing fluid or for adhering by means of suckers: provided with a sucking-organ, whether for imbibing or for adhering; of or pertaining to the Suctoria, in any sense: as, a suctorial bird, fish, worm, insect, crustacean, or animalcule.