- 1[transitive] lighten something to reduce the amount of work, debt, worry, etc. that someone has synonym lessen equipment to lighten the load of domestic work The measures will lighten the tax burden on small businesses.
- 2[intransitive, transitive] to become or make something become brighter or lighter in color The sky began to lighten in the east. lighten something Use bleach to lighten the wood.
- 3[intransitive, transitive] to feel or make someone feel less sad, worried, or serious synonym cheer lighten (up) My mood gradually lightened. lighten something (up) She told a joke to lighten the atmosphere.
- 4[transitive] lighten something to make something lighter in weight Phrasal Verbslighten up
NAmE//ˈlaɪtn//Verb Forms present simple I / you / we / they lighten
he / she / it lightens
past simple lightened
-ing form lightening