noun
(uncountable) A cheerful attitude; happiness; a good, happy, or positive mood.
(now uncountable) That which promotes good spirits or cheerfulness, especially food and entertainment prepared for a festive occasion.
(countable) A cry expressing joy, approval or support, such as "hurrah".
(countable) A chant made in support of a team at a sports event.
(obsolete) One's facial expression or countenance.
(archaic) One's attitude, mood.
verb
(transitive) To gladden; to make cheerful; often with up.
(transitive) To infuse life, courage, animation, or hope, into; to inspirit; to solace or comfort.
(transitive, obsolete) To encourage to do something.
(ambitransitive) To applaud or encourage with cheers or shouts.
(transitive, figurative) To feel or express enthusiasm for (something).
noun
(chiefly Canada, US) Cheerleading, especially when practiced as a competitive sport.