"fascia, fascia-like tendon, white fibrous membrane of the body (often connecting a muscle with a tendon)," 1670s, from Latin, from Greek aponeurosis, from aponeuroein, from apo "change into" (see apo-) + neuron "sinew" (see neuro-).
before vowels ap-, word-forming element meaning "of, from, away from; separate, apart from, free from," from Greek apo "from, away from; after; in descent from," in compounds, "asunder, off; finishing, completing; back again," of time, "after," of origin, "sprung from, descended from; because of," from PIE root *apo- "off, away" (source also of Sanskrit apa "away from," Avestan apa "away from," Latin ab "away from, from," Gothic af, Old English of "away from," Modern English of, off).
before vowels neur-, word-forming element meaning "pertaining to a nerve or nerves or the nervous system," from Greek neura "nerve" (Galen), originally "sinew, bowstring," also neuron "sinew, string (of a bow or musical instrument); cord; penis;" in plural "strength, vigor," from PIE *(s)neuro- "tendon, sinew" (see nerve (n.)). In Greek, puppets were neurospastos, literally "drawn by strings."
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Harper, D. (n.d.). Etymology of aponeurosis. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/aponeurosis