(idiomatic) Periods of positive and negative events, moods, or interactions; highs and lows. / Undulations.

to pursue and apprehend someone or something. / (by extension) to investigate the cause of something

present participle of tip it down

(idiomatic) To garner enthusiastic or wild applause or laughter.

(euphemistic, idiomatic, Britain) Synonym of go down the toilet: to fail; to degenerate rapidly.

(euphemistic, idiomatic, US) Synonym of go down the toilet: to fail; to degenerate rapidly.

(idiomatic) Fundamentally; in essence; in reality

(meteorology, American spelling) A strong, downward air current; an air pocket or air hole.

(transitive) To cause something or someone to pass from a higher to a lower place. / (cricket) To bowl. / (transitive, slang) To commit (someone) to a prison term.

(US, idiomatic, slang, euphemistic) In secret. / (US, idiomatic, slang, euphemistic) Secretly sleeping with someone other than one's partner.