enigmatic

Enigmatic comes from Latin aenigmaticus and French énigmatique, which trace back to Ancient Greek αἰνιγματικός (ainigmatikós). It's built from enigma plus the adjective-forming suffix -tic.

The word has stayed close to its root meaning throughout its path from Greek through Latin and French into English — describing something puzzling or riddle-like.

It shares its root directly with 'enigma,' the noun for a riddle or mystery that enigmatic simply turns into a description.