Home › Words › M › microdrilemicrodrilemicrodrile means any relatively small, generally aquatic, oligochaete, a member of a sometimes used size-based division of the class Oligochaeta.EtymologyFrom Ancient Greek μικρός (mikrós, “small”) + δρῖλος (drîlos, “worm”).nounAny relatively small, generally aquatic, oligochaete, a member of a sometimes used size-based division of the class Oligochaeta.Definitions & examples from Wiktionary (CC BY-SA 3.0).