孔

peacock butterfly (Inachis io); European peacock

green peafowl (Pavo muticus)

Noun or verb acting prenominally

perforated; porous

Zoology

monotremes; Monotremata

Engineering

inner hole

boring machine; punching machine; perforator

needle with a normal eye

porosity

fantail pigeon

Computing

feed hole

arrow slit; arrow-loop; gun loop; gun port

pore; stoma

spiracle; blowhole

Geology

solfatara

test pit; pilot tunnel

Anatomy

foramen ovale; oval foramen of the fetal heart

Anatomy

intervertebral foramen

to pierce a hole

Buddhism

Mahamayuri (deity usu. depicted riding a peacock)

buttonhole

stencil printing; mimeographic printing

Medicine

pupil dilation; mydriasis

Biology

pupillary reflex

the teachings of Confucius and Mencius