moderator

noun

mod·​er·​a·​tor ˈmä-də-ˌrā-tər 

plural moderators

1

: someone who presides over an assembly, meeting, or discussion: such as

a

: the chairperson of a discussion group

b

: a person who administers an online forum, chat room, or group

c

: the nonpartisan presiding officer of a town meeting

d

: the presiding officer of a Presbyterian governing body

2

: one who arbitrates : mediator

3

: a substance (such as graphite) used for slowing neutrons in a nuclear reactor

moderatorship

ˈmä-də-ˌrā-tər-ˌship 

noun

Synonyms of moderator

• chairperson
• president
• chairman
• presider

Examples of moderator in a Sentence

The moderator allowed audience members to ask the governor questions.

She acts as the moderator in our office meetings.

Recent Examples on the Web

Rich Thau, president of Engagious and the moderator of both groups, said some of these voters directly attributed some of their economic concerns to military action abroad. —Ashley Lopez, NPR, 12 Mar. 2026

Monitor stars Brittany O’Grady as Maggie, a young woman haunted by guilt over her sister’s suicide, who spends her days through the most disturbing material on the internet as a content moderator. —Matt Grobar, Deadline, 12 Mar. 2026

The event will feature CBS Los Angeles Anchor Pat Harvey, CBS San Francisco Anchor Ryan Yamamoto, CBS Sacramento Anchor Tony Lopez, CBS News California Investigates correspondent Julie Watts and Pomona College Politics Professor Sara Sadhwani as moderators. —CBS News, 12 Mar. 2026

Even the moderators of fan accounts have had to contend with cascade of attention constantly pummeling the show and its stars — and not all of it has been positive. —Ryan Coleman, Entertainment Weekly, 10 Mar. 2026

Word History

First Known Use

circa 1560, in the meaning defined at sense 2

Rhymes for moderator

• activator
• actuator
• agitator
• alligator
• allocator
• alternator
• animator
• annotator
• applicator
• arbitrator
• aspirator
• aviator

Kids Definition

moderator

noun

mod·​er·​a·​tor ˈmäd-ə-ˌrāt-ər 

1

: one that moderates: as

a

: the leader of a Presbyterian governing body

b

: the chairperson of a town meeting

c

: the chairperson of a discussion group (as on television)

2

: a substance (as graphite) used for slowing down neutrons in a nuclear reactor

Medical Definition

moderator

noun

mod·​er·​a·​tor ˈmäd-ə-ˌrāt-ər 

: a substance (as graphite, deuterium in heavy water, or beryllium) used for slowing down neutrons in a nuclear reactor