D defs.my
Entry 1 sense Webster, 1913

Twinning

· Twin·ning · IPA
01 n. The assemblage of two or more crystals, or parts of crystals, in reversed position with reference to each other in accordance with some def…
  1. 1.
    The assemblage of two or more crystals, or parts of crystals, in reversed position with reference to each other in accordance with some definite law; also, rarely, in artificial twinning (accomplished for example by pressure), the process by which this reversal is brought about.(Crystallog.)
Phrases & compounds
Polysynthetic twinning — repeated twinning of crystal lamellae, as that of the triclinic feldspars.
Repeated twinning — twinning of more than two crystals, or parts of crystals.
Twinning axis — See the Note under Twin, n.