Wiktionary
polycrystalline
a. Composed of an aggregate of very small crystals in random orientations
WordNet
polycrystalline
adj. composed of aggregates of crystals; "polycrystalline metals"
Usage examples of "polycrystalline".
It wouldn't matter what part of the polycrystalline cutting edge touched him.
Her handwriting and underlinings, in scratches of blue lightning on the pad's polycrystalline surface, crowded the computer-generated script she had dialed in from the board.
You see, the atoms of metal form a lattice in three dimensions, which is why metals occur in polycrystalline form—that is, large numbers of small crystals.