say it: LAHY-tuhn
lighten is a verb meaning "make more cheerful". It carries 6 recorded senses.
make more cheerful
“the conversation lightened me up a bit”
become more cheerful
“after a glass of wine, he lightened up a bit”
make more cheerful through the use of color
“The paint will brighten the room”
become lighter
“The room lightened up”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for lighten come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.