Word Study
lightening
OXFORD DICTIONARY
lightening, n. a drop in the level of the womb during the last weeks of pregnancy.
THESAURUS
lightening
abatement, achromatization, allayment, alleviating, alleviation, alleviative, assuagement, blanching, bleach, bleaching, blunting, brightening, calming, damping, deadening, decoloration, decolorization, decolorizing, demulsion, diminution, disburdening, discoloration, disembarrassment, disencumbering, disencumberment, disencumbrance, dulcification, dulling, easement, easing, enlightening, etiolation, fading, falling-off, hushing, illuminating, illumining, leniency, lessening, letdown, letup, lighting, loosening, lulling, madder bleach, market bleach, mitigation, modulation, mollification, pacification, paling, palliation, quietening, quieting, reduction, relaxation, relief, relieving, remission, slackening, softening, soothing, subduement, tempering, tranquilization, unballasting, unburdening, unfreighting, unlading, unloading, unsaddling, untaxing, unweighting, whiteningFor further exploring for "lightening" in Webster Dictionary Online