dropstone

English

Etymology

drop +‎ stone

Noun

dropstone (plural dropstones)

1. (geology) An isolated fragment of rock found within a sedimentary rock (that had fallen, rather than being carried along).
2. (glaciology) An isolated rock that is geologically distinct from the surroundings, indicating that it was carried from a distant area and then dropped in place (by a melting glacier); an erratic.

Synonyms

• (glaciology): erratic

See also

• lonestone