To Gamble
To Bet, To Stake, To Risk
transitive verb, ichidan verb
Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means gamble and the verb vocab version is to gamble.
The reading is the reading you learned with the kanji.
彼女は競馬で、中々の大金を賭けるんだよ。
She gambles considerable amounts of money at the horse races.