Definition of pinacoid in English:

pinacoid

(also pinakoid)

noun

  • In a crystal or crystal structure: a plane or face which intersects one of the crystal axes and is parallel to the other two. Also: a crystal form or solid figure containing two such planes or faces parallel to each other.

adjective

  • Of the nature of a pinacoid; parallel to the two axes that it does not intersect.

Origin

Mid 19th century; earliest use found in James Nicol (1810–1879), geologist. From ancient Greek πινακ-, πίναξ pinax + -oid. With the adjective compare earlier pinacoidal and also Portuguese pinacóide.

Pronunciation

pinacoid

/ˈpɪnəkɔɪd/