The Collaborative International Dictionary of English v.0.48:

Moderate \Mod"er*ate\, v. i.
   1. To become less violent, severe, rigorous, or intense; as,
      the wind has moderated.
      [1913 Webster]

   2. To preside as a moderator.
      [1913 Webster]

            Dr. Barlow [was] engaged . . . to moderate for him
            in the divinity disputation.          --Bp. Barlow's
                                                  Remains
                                                  (1693).
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Moderate \Mod"er*ate\, n. (Eccl. Hist.)
   One of a party in the Church of Scotland in the 18th century,
   and part of the 19th, professing moderation in matters of
   church government, in discipline, and in doctrine.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Moderate \Mod"er*ate\, v. t. [imp. & p. p. Moderated; p. pr. &
   vb. n. Moderating.]
   1. To restrain from excess of any kind; to reduce from a
      state of violence, intensity, or excess; to keep within
      bounds; to make temperate; to lessen; to allay; to
      repress; to temper; to qualify; as, to moderate rage,
      action, desires, etc.; to moderate heat or wind.
      [1913 Webster]

            By its astringent quality, it moderates the relaxing
            quality of warm water.                --Arbuthnot.
      [1913 Webster]

            To moderate stiff minds disposed to strive.
                                                  --Spenser.
      [1913 Webster]

   2. To preside over, direct, or regulate, as a public meeting
      or a discussion; as, to moderate a synod; to moderate a
      debate.
      [1913 Webster +PJC]

The Collaborative International Dictionary of English v.0.48:

Moderate \Mod"er*ate\, a. [L. moderatus, p. p. of moderate,
   moderati, to moderate, regulate, control, fr. modus measure.
   See Mode.]
   Kept within due bounds; observing reasonable limits; not
   excessive, extreme, violent, or rigorous; limited;
   restrained; as:
   (a) Limited in quantity; sparing; temperate; frugal; as,
       moderate in eating or drinking; a moderate table.
   (b) Limited in degree of activity, energy, or excitement;
       reasonable; calm; slow; as, moderate language; moderate
       endeavors.
   (c) Not extreme in opinion, in partisanship, and the like;
       as, a moderate Calvinist; a moderate Republican.
       [1913 Webster]

             A number of moderate members managed . . . to
             obtain a majority in a thin house.   --Swift.
       [1913 Webster]
   (d) Not violent or rigorous; temperate; mild; gentle; as, a
       moderate winter. "Moderate showers." --Walter.
   (e) Limited as to degree of progress; as, to travel at
       moderate speed.
   (f) Limited as to the degree in which a quality, principle,
       or faculty appears; as, an infusion of moderate strength;
       a man of moderate abilities.
   (g) Limited in scope or effects; as, a reformation of a
       moderate kind. --Hooker.
       [1913 Webster]

WordNet (r) 3.0 (2006):

moderate
    adj 1: being within reasonable or average limits; not excessive
           or extreme; "moderate prices"; "a moderate income"; "a
           moderate fine"; "moderate demands"; "a moderate
           estimate"; "a moderate eater"; "moderate success"; "a
           kitchen of moderate size"; "the X-ray showed moderate
           enlargement of the heart" [ant: immoderate]
    2: not extreme; "a moderate penalty"; "temperate in his response
       to criticism" [syn: moderate, temperate]
    3: marked by avoidance of extravagance or extremes; "moderate in
       his demands"; "restrained in his response" [syn: moderate,
       restrained]
    n 1: a person who takes a position in the political center [syn:
         centrist, middle of the roader, moderate,
         moderationist]
    v 1: preside over; "John moderated the discussion" [syn:
         moderate, chair, lead]
    2: make less fast or intense; "moderate your speed"
    3: lessen the intensity of; temper; hold in restraint; hold or
       keep within limits; "moderate your alcohol intake"; "hold
       your tongue"; "hold your temper"; "control your anger" [syn:
       control, hold in, hold, contain, check, curb,
       moderate]
    4: make less severe or harsh; "He moderated his tone when the
       students burst out in tears" [syn: mince, soften,
       moderate]
    5: make less strong or intense; soften; "Tone down that
       aggressive letter"; "The author finally tamed some of his
       potentially offensive statements" [syn: tone down,
       moderate, tame]
    6: restrain [syn: chasten, moderate, temper]

Moby Thesaurus II by Grady Ward, 1.0:

372 Moby Thesaurus words for "moderate":
   K, Laodicean, abate, acceptable, accepting, act between, adequate,
   adjust to, admissible, all right, allay, alleviate, alter, ambling,
   apathetic, arbitrate, arrest, assuage, attemper, average,
   backpedal, backwater, balanced, banal, bank the fire, bargain,
   better than nothing, betwixt and between, bland, blunt, bound,
   box in, brake, budget, calm, cautious, center, central, centrist,
   chair, chasten, cheap, check, circumscribe, circumspect,
   claudicant, clement, clip the wings, common, compassionate,
   compromiser, condition, confine, conservative, constant, constrain,
   contain, control, controlled, cool, coordinate, copyright,
   crawling, creeping, creeping like snail, curb, cushion, damp,
   dampen, de-emphasize, deaden, decelerate, decent, decrease, defuse,
   delay, deliberate, detain, diminish, direct, discipline, discreet,
   downplay, draw rein, draw the line, dull, ease, ease off, ease up,
   easy, easygoing, ebb, economic, economy, equable, even, extenuate,
   fair, fair to middling, fairish, fall, faltering, fifty-fifty,
   flagging, foot-dragging, forbearant, forbearing, forgiving, frugal,
   gentle, go between, good enough, goodish, gradual, grave,
   half-and-half, halting, hedge, hedge about, hobbled, hobbling,
   hold back, hold in check, hold up, humane, idle, impartial, impede,
   inconsequential, inconsiderable, independent, indifferent,
   indolent, inexpensive, insipid, intercede, intermediary,
   intermediate, interpose, intervene, judge, judicious, keep back,
   keep within bounds, lackluster, languid, languorous, lax, lay,
   lazy, leaven, leisurely, lenient, lenify, lessen, let down, let up,
   let up on, lighten, limit, limping, lose ground, lose momentum,
   lose speed, low, low-priced, lumbering, make terms, manage,
   manageable, mean, measured, medial, median, mediate, mediocre,
   medium, meet halfway, merciful, middle, middle-of-the-road,
   middle-of-the-roader, middling, midway, mild, mild as milk,
   mitigate, moderantist, moderationist, moderatist, modest, modify,
   modulate, mollify, namby-pamby, narrow, negotiate, neuter, neutral,
   nominal, nonaligned, noncommitted, nonpartisan, nonviolent, normal,
   not amiss, not bad, not half bad, not so bad, obstruct, obtund,
   of a kind, of a sort, of sorts, okay, on the fence, ordinary,
   pacifistic, palliate, paltry, passable, passive, patent, patient,
   peaceable, peaceful, piddling, play down, poking, poky,
   presentable, preside over, pretty good, prudent, qualify, rational,
   reasonable, reduce, reduce the temperature, reef, referee,
   register, regulate, regulate by, rein in, relax, relaxed, relent,
   relieve, reluctant, remit, represent, respectable, restrain,
   restrained, restrict, retard, routine, run, satisfactory,
   sauntering, scant, season, sedate, sensible, serious, set back,
   set conditions, set limits, shabby, shoddy, shuffling, slack,
   slack off, slack up, slacken, slight, slothful, slow,
   slow as death, slow as molasses, slow as slow, slow down, slow up,
   slow-crawling, slow-foot, slow-going, slow-legged, slow-moving,
   slow-paced, slow-poky, slow-running, slow-sailing, slow-stepped,
   sluggish, small, smother, snail-paced, snaillike, so-so, sober,
   sober down, sober-minded, sobersided, soft, soft-shell, soften,
   solemn, soothe, sparing, specialize, staggering, staid, standard,
   stay, steady, step in, stifle, stint, stinting, straiten,
   strolling, subdue, subside, sufficient, supervise, suppress,
   take in sail, tame, tedious, temper, temperate, tender, tentative,
   third-force, third-world, throttle down, tidy, toddling, token,
   tolerable, tolerant, tone down, tortoiselike, tottering,
   treat with, trifling, trivial, trudging, tune down, turtlelike,
   umpire, uncommitted, underplay, unexceptionable, unexceptional,
   unexcessive, unexpensive, unextreme, unhurried, unimpassioned,
   uninvolved, unobjectionable, usual, vapid, waddling, wane, weaken,
   wishy-washy, within means, workmanlike, worth the money