the action, treated as a criminal offence, of demanding payment or another benefit from someone in return for not revealing compromising or damaging information about them.
they were acquitted of charges of blackmail
extortion,demanding money with menaces,exaction,intimidation,protection racket,bribery,wringing,milking,bleeding,bloodsucking,hush money,chantage
demand money or another benefit from (someone) in return for not revealing compromising or damaging information about them.
they use this fact to blackmail him, trying to force him to vote for their candidate
extort money from,threaten,hold to ransom,milk,bleed,demand hush money from