fenestra

fenestra (noun; plural fenestrae; Latin fenestra, window): 1. A small opening; a window.

2. An opening through a shell; a foramen.

3. (Arthropoda: Insecta) a. Transparent spots or marks on the wings. b. In Orthoptera, a small membranous area at the base of an antennae of a cockroach. c. In Isoptera, a cavity on the head; a fontanel. d. The membranous base of the ommatidia at the junction with the optic nerve of a compound eye; a transparent ocellate spot in an eye. e. In male Odonata, the genital opening on the ventral surface of abdominal segment 11

See also: fontanelle. 4. (Bryozoa: Gymnolaemata) In Cheilostomata, an open space or mesh in reticulate zoaria. 5. (NEMATA) a. In Secernentea, the thin membranous area surrounding or on either side of the vulva of a cyst forming nematode (Heterodera spp.). b. In some marine Adenophorea, the openings in subcuticular helmets through which sensory nerves pass.