fə̇ˈnestrə noun
( plural fenes·trae -ˌstrē, -ˌstrī)
Etymology: New Latin, from Latin, opening in a wall for air and light, window
1. anatomy : a small opening ; especially : either of two membrane-covered apertures in the bone between the middle and inner ear: (1) an oval opening between the middle ear and the vestibule having the base of the stapes or columella attached to its membrane and (2) a round opening between the middle ear and the cochlea — called also respectively (1) fenestra ova.lis -ōˈvälə̇s, -vāl-, -val- or fenestra ves.ti.bu.li -veˈstibyəˌlī and (2) fenestra ro.tun.da -rōˈtəndə or fenestra coch.le.ae -ˈkäklēˌē, -lēˌī
2.
a. : an opening like a window cut in bone (as in the inner ear in the fenestration operation)
b. : a window cut in a surgical instrument (as an endoscope)
3.
a. : a transparent spot (as in the wings of certain moths)
b. : one of two pits covered with membrane on the head of certain cockroaches
c. : the fontanel of a termite