plane group

plane group

[′plān ‚grüp]
(crystallography)
The group of operations (rotations, reflections, translations, and combinations of these) which leave a regular, periodic structure in a plane unchanged.
(mathematics)
One of 17 two-dimensional patterns which can be produced by one asymmetric motif that is repeated by symmetry operations to produce a pattern unit which then is repeated by translation to build up an ordered pattern that fills any two-dimensional area. Also known as plane symmetry group.
References in periodicals archive ?
"Noting that while passing by the unit, he abruptly dropped in at the unit in order to learn about the flight drill of a pursuit assault plane group, Kim said it is important to make a sudden inspection of the regular readiness of unit as a fight of the air and anti-aircraft field is waged without previous notice," KCNA said.