An Etymological Dictionary of Astronomy and Astrophysics

The highest point or upper part of a wave.

Etymology (EN): From O.Fr. creste “tuft, comb,” from L. crista “tuft, plume; rooster’s comb.”

Etymology (PE): Setiq “summit; anything standing upright,” from O.Pers./Av. sta- “to stand, stand still; set,” Mod.Pers. istâdan “to stand”
(cf. Skt. sthâ- “to stand,” Gk. histemi “put, place, weigh,” stasis “a standing still,” L. stare “to stand”)

• adj. suffix -iq, variants -ig, -ik, → -ics.