Definition of ear cockle in US English:

ear cockle

noun

  • A disease of wheat and other cereal plants caused by the parasitic nematode Anguina tritici, in which the grains are replaced by small, dark galls. Also (in plural): the galls themselves.

Origin

Late 18th century; earliest use found in The Gentleman's Magazine. From ear + cockle, possibly after the resemblance of the galls to the black seeds of the corncockle, Agrostemma githago.

Pronunciation

ear cockle

/ˈɪə kɒkl/