bone of contention

noun

1. a subject, cause, or focal point of a dispute.

   The terms of the old man's will were a bone of contention to his survivors.

bone of contention

noun

1. the grounds or subject of a dispute

Word History and Origins

Origin of bone of contention¹

First recorded in 1705–15

Idioms and Phrases

Main issue of a disagreement; something to quarrel about. For example, Grandfather's will was a bone of contention for the whole family. This expression alludes to two dogs fighting (contending) over a single bone. In slightly different guise, bone of dissension, it was used figuratively in the 16th century and took its present form in the early 1700s.