1.
no way; you're kidding; that can't be true
A casual exclamation expressing disbelief or shock. Literally 'that's a lie, right?' Used when hearing something surprising or hard to believe.
嘘だろ！信じられない。
No way! I can't believe it.
試験に落ちた？嘘だろ。
You failed the exam? You're kidding.
明日の試合が中止だって？嘘だろ、ずっと楽しみにしてたのに。
Tomorrow's game is cancelled? No way — I was looking forward to it the whole time.
An extremely common casual expression in spoken Japanese. The tone can range from genuine shock to mild surprise. Considered masculine-leaning; female speakers more often use 嘘でしょ or 嘘！
VARIATIONS:
- 嘘だろ: casual masculine (plain)
- 嘘でしょ: slightly softer, used by both genders
- 嘘でしょう: more polite
- 嘘！: short exclamation (very common among women)
- マジで？: "seriously?" (similar function, very casual)
USAGE NOTE:
Despite containing 嘘 (lie), this expression does not accuse anyone of lying. It simply expresses the speaker's disbelief at surprising information.