snowflake

Colloquially an ice crystal, or more commonly an aggregation of many crystals that falls from a cloud. In the latter case, the snowflake may be referred to as an aggregate.

Simple snowflakes (single crystals) exhibit beautiful variety of form, but the symmetrical shapes reproduced so often in photomicrographs are not found frequently in snowfalls. Broken single crystals, fragments, or clusters of such elements are much more typical of actual snow. Snowflakes (aggregates) made up of clusters of crystals (many thousand or more) or crystal fragments may grow as large as three to four inches in diameter, often building themselves into hollow cones falling point downward. In extremely still air, flakes with diameters as large as 10 inches have been reported.

Term edited on 12 May 2026.