Moderator
/ˈmɒdəreɪtər/
Definitions
2 meaningsA person who leads or controls a discussion or event.
/ˈmɒdəreɪtər/
A person who presides over a meeting, discussion, or debate.
The debate moderator made sure each candidate had an equal amount of time.
💡 Simply: Imagine a referee in a game, or a host of a TV show; they make sure everything goes smoothly and that everyone gets a chance to speak. That's a moderator!
👶 For kids: The person who helps keep things fair in a discussion.
More Examples
The online forum moderator deleted posts that violated the rules.
She was chosen as the moderator of the town hall meeting because of her neutrality.
How It's Used
"The moderator kept the debate civil and on topic."
"A professor served as the moderator for the student panel."
"The moderator removed any offensive content from the forum."
A material that slows down neutrons in a nuclear reactor.
/ˈmɒdəreɪtər/
A substance used to slow down neutrons in a nuclear reactor.
The type of moderator used in the reactor affects its efficiency.
💡 Simply: In a nuclear reactor, there's something called a 'moderator' which is like a speed bump for tiny particles, called neutrons, to help them work efficiently.
👶 For kids: A special stuff that helps slow down some tiny parts in a nuclear reactor.
More Examples
Heavy water can act as a moderator in nuclear fission.
Neutrons interact with the moderator, slowing them down so they are more likely to cause further fission.
How It's Used
"Graphite is a common moderator used in nuclear reactors."
Idioms & expressions
moderator effect
A variable that influences the strength or direction of the relationship between two other variables.
"The study investigated the moderator effect of income on the relationship between education and health outcomes."
From Latin *moderātor*, from *moderārī* ('to regulate, control').
The term has been used since the 17th century to describe someone who presides over a meeting. Its use in physics to describe neutron moderators is a later, more specialized development.
Memory tip
Think of a traffic controller. The moderator 'controls' the flow.