12 letters · 13 points in Scrabble
noun a shrill grating or chirping noise made by some insects by rubbing body parts together
origin1838, from earlier term stridulous; from Latin strīdulus (“giving a shrill sound, creaking”), from strīdō (“utter a shrill or harsh sound; creak, shriek, grate, hiss”).
Etymology from Wiktionary, CC BY-SA 3.0