to lessen in force or intensity, as wrath, grief, harshness, or pain; moderate.
to make less severe: to mitigate a punishment.
to make (a person, one's state of mind, disposition, etc.) milder or more gentle; mollify; appease.
verb (used without object),mit·i·gat·ed,mit·i·gat·ing.
to become milder; lessen in severity.
Origin of mitigate
1375–1425;late Middle Englishmitigaten < Latinmītigātus (past participle of mītigāre to calm, soften, soothe), equivalent to mīt(is) mild, soft, gentle + -ig- (combining form of agere to do, cause to do, make) + -ātus-ate1
Related formsmit·i·ga·ble[mit-i-guh-buh l]/ˈmɪt ɪ gə bəl/, adjectivemit·i·gat·ed·ly, adverbmit·i·ga·tion, nounmit·i·ga·tive, mit·i·ga·to·ry[mit-i-guh-tawr-ee, -tohr-ee]/ˈmɪt ɪ gəˌtɔr i, -ˌtoʊr i/, adjectivemit·i·ga·tor, nounnon·mit·i·ga·tive, adjectivenon·mit·i·ga·to·ry, adjectiveo·ver·mit·i·gate, verb,o·ver·mit·i·gat·ed,o·ver·mit·i·gat·ing.un·mit·i·ga·ble, adjectiveun·mit·i·ga·tive, adjectiveCan be confusedmilitatemitigate (see usage note at the current entry)
Mitigate, whose central meaning is “to lessen” or “to make less severe,” is sometimes confused with militate, which means “to have effect or influence; weigh on.” This mix-up often occurs in the use of the phrase mitigate against, as follows: This criticism in no way mitigates (read militates ) against your going ahead with your research. Although this use of mitigate occasionally occurs in edited writing, it is rare and is widely regarded as an error.
early 15c., "relieve (pain)," from Latin mitigatus, past participle of mitigare "soften, make tender, ripen, mellow, tame," figuratively, "make mild or gentle, pacify, soothe," ultimately from mitis "gentle, soft" (from PIE *mei- "mild") + root of agere "do, make, act" (see act). First element is from PIE root *mei- "soft, mild." Related: Mitigated; mitigating; mitigates.