əˈthē(ˌ)sē noun plural
Usage: capitalized
Etymology: New Latin, from feminine plural of (assumed) New Latin athecus having no cover, from New Latin a- (II) + (assumed) New Latin -thecus (from Latin theca cover, sheath) — more at tick
: a division usually made a suborder of Testudinata comprising turtles with the carapace separate from the internal skeleton and usually with greatly reduced ossification and represented among recent forms by the marine leatherback
• athe·can -ēkən adjective or noun