"not excessive in amount, intensity, quality, etc.," late 14c., originally of weather and other physical conditions, from Latin moderatus "within bounds, observing moderation;" figuratively "modest, restrained," past participle of moderari "to regulate, mitigate, restrain, temper, set a measure, keep (something) within measure," from PIE *med-es-, from root *med- "take appropriate measures." The notion is "keeping within due measure." In English, of persons from early 15c., of opinions from 1640s, of prices from 1670s. Related: Moderateness.
early 15c., "to abate excessiveness, reduce the intensity of;" from Latin moderatus "within bounds, observing moderation;" figuratively "modest, restrained," past participle of moderari "to regulate, mitigate, restrain, temper, set a measure, keep (something) within measure," from PIE root *med- "take appropriate measures." Intransitive sense of "become less violent, severe, rigorous, etc." is from 1670s. Meaning "to preside over a debate" is first attested 1570s. Related: Moderated; moderating.
"one who holds moderate opinions on controversial subjects, one who is opposed to extreme views or courses," 1794 (Burke), from moderate (adj.). Related: Moderatism.
word-forming element used in forming nouns from Latin words ending in -atus, -atum (such as estate, primate, senate). Those that came to English via French often arrived with -at, but an -e was added after c. 1400 to indicate the long vowel. The suffix also can mark adjectives formed from Latin past participles in -atus, -ata (such as desolate, moderate, separate); again, they often were adopted in Middle English as -at, with an -e appended after c. 1400.
Proto-Indo-European root meaning "take appropriate measures."
It forms all or part of: accommodate; accommodation; commode; commodious; commodity; empty; immoderate; immodest; Medea; medical; medicament; medicaster; medicate; medication; medicine; medico; medico-; meditate; meditation; Medusa; meet (adj.) "proper, fitting;" mete (v.) "to allot;" modal; mode; model; moderate; modern; modest; modicum; modify; modular; modulate; module; modulation; mold (n.1) "hollow shape;" mood (n.2) "grammatical form indicating the function of a verb;" must (v.); premeditate; premeditation; remedial; remediation; remedy.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit midiur "I judge, estimate;" Avestan vi-mad- "physician;" Greek mēdomai "be mindful of," medesthai "think about," medein "to rule," medon "ruler;" Latin meditari "think or reflect on, consider," modus "measure, manner," modestus "moderate," modernus "modern," mederi "to heal, give medical attention to, cure;" Irish miduir "judge;" Welsh meddwl "mind, thinking;" Gothic miton, Old English metan "to measure out."
c. 1300, "moderate, modest, discreet" (a sense now obsolete), from Old French mesurable "restrained, moderate, sensible; restricted," from Late Latin mensurabilis, from mensurare "to measure," from Latin mensura "a measuring, a measurement; thing to measure by," from mensus, past participle of metiri "to measure," from PIE root *me- (2) "to measure." Meaning "that can be measured" is from mid-14c. Related: Measurably.