bone of contention

/boʊn əv ˈkɑnˌtɛnʃən/
noun phrase★Intermediate💡 main source of dispute◆idiom
◆ What It Really Means
A persistent and often petty issue that causes ongoing conflict or disagreement between people.
Literal Meaning
A literal bone that two or more animals are fighting over.
Literal Breakdown
bonea hard, calcified organ that forms part of the skeleton+of contentiondisputing or arguing over possession or control
◇ Mental Image
The mental picture is of two dogs growling and snapping at each other over a single bone, unable to share or compromise. This vivid image emphasizes the futility and stubbornness often associated with the conflicts described by the idiom.
◈ When to Use
Imagine two coworkers arguing for weeks over who gets to use the corner office with the better view. Their manager finally says, 'The corner office shouldn't be the bone of contention between you two.'
◉ Cultural Note
The phrase is deeply rooted in English-speaking cultures, where the image of animals fighting over food is universally understood. While the idiom itself is not offensive, it carries a slightly humorous or critical tone, implying the conflict is unnecessary or trivial.
formal

the main subject or issue causing ongoing disagreement or conflict

The division of the inheritance was the bone of contention in the family meeting.

The family argued over how to split the inheritance.

The new parking policy became the bone of contention at the condo association.

Residents fiercely debated the parking policy changes.

💡

Used for both personal and professional conflicts. Often implies the issue is trivial or unnecessary.

Collocations

become the bone of contentionto be the main source of conflictserve as the bone of contentionto function as the primary cause of disagreement

Related Phrases

bone of discordidiom
a cause of disagreement or conflict
make common causephrase
to unite for a shared purpose
settle a scorephrase
to resolve a grievance or conflict

💡Pro Tip

When to use this idiom

Use 'bone of contention' when describing the main issue causing tension in a group. It works for both serious conflicts (e.g., legal disputes) and minor ones (e.g., roommate disagreements). Avoid using it for physical conflicts or life-or-death situations.

⚡Gold Rule

Article usage

Always use 'the' before 'bone of contention' (e.g., 'the bone of contention'). Omitting 'the' is incorrect.

Plural form

The idiom is always singular. Do not say 'bones of contention' unless referring to multiple separate disputes.

📖Word Origin

From the literal sense of a bone causing pain or conflict between animals (or people) fighting over it. The phrase dates back to the 16th century, with 'bone of contention' appearing in English by the 17th century. The idiom likely originates from the image of two dogs fighting over a single bone.

📝Usage Notes

This idiom is used in both formal and informal contexts to describe any persistent disagreement, regardless of scale. It often implies the issue is petty or avoidable. The phrase is always used with the definite article 'the' (e.g., 'the bone of contention').

Word Breakdown

bone
a hard, rigid part of the skeleton
literal
+
of contention
causing argument or dispute
figurative
English Dictionary