1. any substance used to slow down neutrons in nuclear reactors
2. in the Presbyterian church, the officer who presides over a synod or general assembly
3. someone who presides over a forum or debate
4. someone who mediates disputes and attempts to avoid violence
The Collaborative International Dictionary of English v.0.48:
Moderator \Mod"er*a`tor\, n. [L.: cf. F. mod['e]rateur.]
1. One who, or that which, moderates, restrains, or pacifies.
--Sir W. Raleigh.
Angling was . . . a moderator of passions. --Walton.
2. The officer who presides over an assembly or discussion to
preserve order, propose questions, regulate the
proceedings, and declare the votes.
3. In the University of Oxford, an examiner for moderations;
at Cambridge, the superintendant of examinations for
degrees; at Dublin, either the first (senior) or second
(junior) in rank in an examination for the degree of
Bachelor of Arts.
4. A mechanical arrangement for regulating motion in a
machine, or producing equality of effect.
WordNet (r) 3.0 (2006):
n 1: any substance used to slow down neutrons in nuclear
2: in the Presbyterian church, the officer who presides over a
synod or general assembly
3: someone who presides over a forum or debate
4: someone who mediates disputes and attempts to avoid violence
Moby Thesaurus II by Grady Ward, 1.0:
57 Moby Thesaurus words for "moderator":
JP, Justice, MC, alleviative, alleviator, anchorman, anodyne,
arbiter, arbitrator, assuager, balm, bencher, calmative, chair,
chairman, conciliator, coordinator, critic, cushion, dolorifuge,
emcee, his honor, his lordship, his worship, impartial arbitrator,
indicator, judge, justice, lenitive, magistrate,
master of ceremonies, mediator, mitigator, modulator, mollifier,
negotiator, pacificator, pacifier, palliative, peacemaker,
president, presiding officer, referee, restraining hand, salve,
sedative, shock absorber, soother, soothing syrup, stabilizer,
temperer, third party, toastmaster, tranquilizer, umpire,
unbiased observer, wiser head
The Free On-line Dictionary of Computing (18 March 2015):
A person, or small group of people, who manages a moderated
mailing list or Usenet newsgroup. Moderators are
responsible for determining which email submissions are passed
on to the list or newsgroup.
Bouvier's Law Dictionary, Revised 6th Ed (1856):
MODERATOR. A person appointed to preside at a popular meeting; sometimes he
is called a chairman.