co-worker

IPA/ˈkəʊ wɜːkə(r)/
KK[kˈowˈɚkɚ]IPA/ˈkəʊ wɜːrkər/

co-worker — noun

1. someone employed at the same workplace as you, usually doing a job at roughly th

1.nounB1
Definition

someone employed at the same workplace as you, usually doing a job at roughly the same rank rather than being your boss or junior staff.

Example

Sofia invited two co-workers from the design team to her wedding next month.

co-workers from + [team/department]

Christopher rides the train to the office every morning with a co-worker who lives nearby.

singular: a co-worker who…

Common collocations
  • former co-worker
  • fellow co-worker
  • trusted co-worker
  • co-worker from [department]
Synonyms
  • colleague

    more common in British English and in formal or professional writing

  • workmate

    informal British English; often suggests friendly, casual ties

  • associate

    more formal; used in business or legal contexts

  • teammate

    stresses working together on the same project or team

Antonyms
  • boss

    the person you report to, not a peer

  • supervisor

    directly oversees your work

Grammar Patterns

a co-worker of [person]

[person]'s co-worker

Usage Note

Refers to peers, not bosses or subordinates — for those, use 'manager', 'supervisor', or 'junior staff'. American spelling 'coworker' (no hyphen) is increasingly common; British texts more often use 'colleague'.

Common Mistakes

My co-worker fired me last week.
My boss fired me last week.
a co-worker is a peer, not someone with authority over you.
I have many co-workers in my school.
I have many classmates in my school.
co-worker is for paid workplaces, not schools.

Word family

Synonym discussion

Sense: noun/1

All four words describe people you work with, but they fit different settings. 'Co-worker' is neutral and common in American English, simply naming someone employed at the same place as you. 'Colleague' is preferred in British English and in formal writing; it can also extend beyond one company — a doctor might call another doctor at a different hospital a colleague. 'Workmate' is informal British English and usually suggests friendly, casual ties, often among manual or service workers. 'Associate' is the most formal of the four, common in law firms, banks and business titles (e.g. 'sales associate'). Compare: 'Sofia and her co-workers grabbed lunch' (everyday workplace), 'Dr. Lin discussed the case with a colleague in Taipei' (professional, cross-company), and 'the senior associate signed the contract' (formal job role).

co-worker ↗colleague ↗workmateassociate ↗

Common collocations

Nouns

  • co-worker friendship
  • co-worker relationship

Phrases

  • former co-worker
  • fellow co-worker
  • trusted co-worker
  • close co-worker

Prepositions

  • co-worker of
  • co-worker at
  • co-worker from

Etymology

LatinOld EnglishEnglish

Formed in English in the mid-1600s by joining the prefix 'co-' (meaning 'together with', from Latin 'cum') to the noun 'worker'. The hyphenated spelling 'co-worker' was standard for centuries, but the unhyphenated 'coworker' has grown common in American English since the late 20th century, mirroring the same trend with words like 'cooperate' and 'coordinate'.