An act of deceiving someone to obtain money or goods; fraud, swindle, or scam (used in legal and everyday contexts).
オレオレ詐欺の被害がまた増えている。
Victims of the 'It's me' phone scam are increasing again.
ネットオークションで詐欺に遭ってしまった。
I was scammed on an online auction.
その会社は詐欺の疑いで捜査を受けている。
The company is under investigation on suspicion of fraud.
Colloquially used to complain that something is unfair, a rip-off, or that someone broke a promise (e.g., 'that's a rip-off', 'you stood me up').
そんな高い値段は詐欺だよ。
That price is a rip-off.
約束しておいて来ないなんて詐欺みたいだ。
Making a promise and not coming is like a scam.