mantis (n.)
1650s, "type of insect that holds its forelegs in a praying position" (especially the praying mantis, Mantis religiosa), Modern Latin, from Greek mantis, literally "one who divines, a seer, prophet," from mainesthai "be inspired," related to menos "passion, spirit," from PIE *mnyo-, suffixed form of root *men- (1) "to think," with derivatives referring to qualities and states of mind or thought. (compare mania and -mancy). The insect so called for its way of holding the forelimbs as if in prayer. Also used in Greek for some sort of grasshopper (Theocritus).