Definition of polyomino in English:

polyomino

Pronunciation /ˌpɒlɪˈɒmɪnəʊ/

noun

Geometry
  • A planar shape formed by joining a number of identical squares by their edges.

Origin

1950s; earliest use found in American Mathematical Monthly. From poly- + -omino; compare pentomino (and the etymological discussion at that entry).