complainant

noun

com·​plain·​ant kəm-ˈplā-nənt 

1

: the party who makes the complaint in a legal action or proceeding

2

: one who complains

Synonyms

• plaintiff

Examples of complainant in a Sentence

the complainant charged that the defendant had broken the ironclad contract that both had signed

Recent Examples on the Web

The commission did not update complainants on the investigation process in any of the complaints the auditor reviewed. —Cody Copeland, Fort Worth Star-Telegram, 23 June 2025

The second complainant’s account is similar, the BBC added. —Max Goldbart, Deadline, 16 June 2025

The first incident occurred in April 2020, when Pitt allegedly forcibly touched the complainant’s genitals. —Alexandra Del Rosario, Los Angeles Times, 7 May 2025

In the years that followed there have been a number of civil suits brought by female complainants against Cuomo that have not been resolved. —New York Daily News Editorial Board, New York Daily News, 20 June 2025

Word History

First Known Use

15th century, in the meaning defined at sense 1

Kids Definition

complainant

noun

com·​plain·​ant kəm-ˈplā-nənt 

1

: one who makes a legal complaint

2

: one who complains

Legal Definition

complainant

noun

com·​plain·​ant kəm-ˈplā-nənt 

: the party (as a plaintiff or petitioner) who makes the complaint in a legal action or proceeding