keep someone at arm's length

Meaning

This idiom means to avoid becoming too friendly, close, or intimate with someone, maintaining a safe emotional or physical distance. It is commonly used in both personal relationships and professional environments to establish boundaries or protect oneself from potential drama or conflict. The tone is neutral and pragmatic.

Examples

• After they broke up, she decided to keep him at arm's length.

  After they broke up, she decided to keep him at arm's length.

• It's best to keep competitive colleagues at arm's length in this industry.

  It's best to keep competitive colleagues at arm's length in this industry.

• He is a nice guy, but I prefer to keep my neighbors at arm's length.

  He is a nice guy, but I prefer to keep my neighbors at arm's length.

• She kept her new boss at arm's length until she could trust his intentions.

  She kept her new boss at arm's length until she could trust his intentions.

• I try to keep toxic family members at arm's length for my own peace of mind.

  I try to keep toxic family members at arm's length for my own peace of mind.

Common Mistakes

• ✗ I kept him at my arm length.

  ✓ I kept him at arm's length.

  The idiom uses the singular possessive 'arm's' and does not take a personal pronoun like 'my' or 'his' before 'arm'.

• ✗ She keeps her coworkers on arm's length.

  ✓ She keeps her coworkers at arm's length.

  The correct preposition is 'at', which indicates distance, not 'on'.

Related Expressions

Practice

• To avoid office gossip, it's wise to keep your teammates at ___ length.

  💡 Don't forget the apostrophe-s.

  Show answer

  arm's

• She has been keeping me ___ arm's length ever since our argument.

  💡 The preposition used to show distance.

  Show answer

  at