sigmate

From sigma +‎ -ate (adjective-forming suffix).

sigmate (comparative more sigmate, superlative most sigmate)

1. Shaped like the Greek letter sigma.

• sigmatic
• sigmoid

From sigma +‎ -ate (verb-forming suffix).

sigmate (third-person singular simple present sigmates, present participle sigmating, simple past and past participle sigmated)

1. (transitive, grammar) To modify (a Greek word) by adding a sigma, or by changing another letter to sigma.

• gamiest, gemista