brittle (adj.)
late 14c., britel, perhaps from an unrecorded Old English adjective *brytel, related to brytan "to crush, pound, to break to pieces," from Proto-Germanic stem *brutila- "brittle," from *breutan "to break up" (cognates: Old Norse brjota "to break," Old High German brodi "fragile"), from PIE *bhreu- "to cut, break up" (see bruise (v.)). With -le, suffix forming adjectives with meaning "liable to."