Green’s Dictionary of Slang

1. (US campus) to get the grade ‘B’ on a test or examination.

1969

in Current Sl. IV:3–4 (1970).

2. (US campus) to perform badly in an examination.

1967–8		Baker et al. CUSS 84: Bombed out Do poorly on an exam.
1978		Eble Campus Sl. Apr. 1: bombed – to do poorly [...] I bombed the last exam.

3. (US) to fail, to do badly; also bomb out v. (1)

[1532		T. More Confutation of Tyndale Answer VIII Pt II 741: Lo good reder here shall ye se that the thynge where about he hath bombed all this whyle, that is to proue that he knoweth not the scrypture by the chyrche].
1962		S. Longstreet Flesh Peddlers (1964) 162: For old times sake I let him handle something I’ve been setting up for a year. He bombed.
1976		N. Thornburg Cutter and Bone (2001) 178: Face it, lady. We bombed.
1984		C. White Life and Times of Little Richard 137: He thought for a minute that we’d bombed, but when they realized what was happening they just went wild.
1995		D. Lodge Therapy (1996) 69: The BBC show bombed.
2006		C. Hiaasen Nature Girl 167: Her speech had bombed and now the whole plan seemed depressingly misguided.
2011		IOL News 6 Dec. 🌐 Lunch started off fabulously, but main course bombed.
2020		C. von Ziegesar Cobble Hill 66: [H]e'd had a crush on his math teacher. He'd bombed every test just so he could stay after school [...] and be alone with her .

4. (US, also bomb off) of machinery or other equipment, to break down, to malfunction.

1975

G. Underwood ‘Razorback Sl.’ in AS L:1/2 56: bomb off vi Fail to work (typically said of a computer program).

5. (Aus.) to fail at.

1986

R.G. Barrett Real Thing 141: If I get in there and have a lash at her it’s going to be a hurried job [...] and I could bomb the rort.

6. of an experience, to be bad or disappointing.

1997–2001

Online Sl. Dict. 🌐 bomb v [...] 2. to be disappointing. (‘That party bombed.’).