Nouns

(n)cheera cry or shout of approval
(n)cheerfulness, cheer, sunniness, sunshinethe quality of being cheerful and dispelling gloom“flowers added a note of cheerfulness to the drab room”

Verbs

(v)cheer, hearten, recreate2, emboldengive encouragement to
(v)cheershow approval or good wishes by shouting“everybody cheered the birthday boy”
(v)cheer, cheer up, jolly along, jolly upcause (somebody) to feel happier or more cheerful“She tried to cheer up the disappointed child when he failed to win the spelling bee”
(v)cheer, cheer up, chirk upbecome cheerful
(v)cheer, root on, inspire, urge, barrack, urge on, exhort, pep upspur on or encourage especially by cheers and shouts“The crowd cheered the demonstrating strikers”