Green’s Dictionary of Slang

1. a cyclist.

1895

‘’Arry and the [...] Lady Cyclists’ in Punch 15 June 285/1: dear charlie, — you know I’m a ‘biker,’ I told yer a good bit ago.

2. (orig. US) a motorcycle rider, usu. a member of an outlaw motorcycle gang.

1968		Harper’s Mag. Nov. 96: The Yippies came out of the Hippies, ex-Hippies, diggers, bikers, drop-outs from colleges, hipsters up from the South.
1976		C. Keane Hunter 57: Papa could understand Richie bailing out motorcycle gang members—bikers— who were not as insane as Boom Boom.
1983		C. Heath A-Team 2 (1984) 108: Jenko was there with his gang of bikers.
1997		(con. 1970s) G. Pelecanos King Suckerman (1998) 22: Brokering a deal between those Southern boys [...] and the Howard County bikers.
1998		G. Burn Happy Like Murderers 49: All the first intake of lodgers were male; hippies or bikers, Hell’s Angels types.
2007		N. McCall Them (2008) 17: A bunch of long-haired bikers – a motorcycle gang! – with flags pasted across their sleeveless leather jackets.
2011		Times 10: It’s bad-ass bikers doing bad-ass things.
2020		D. Winslow ‘Paradise’ in Broken 258: Killed a biker in his last stint [in prison].

3. attrib. use of sense 2.

1978		A. Maupin Tales of the City (1984) 108: This couple waltzed in and took a seat in the middle of a heavy biker contingent.
1987		‘Joe Bob Briggs’ Joe Bob Goes to the Drive-In 185: Okay, we all know the great biker flicks, right, starting in 54 with The Wild One.
1995		J. Stahl Permanent Midnight 292: College dropout, biker moll, borderline coke whore.
1997		‘Q’ Deadmeat 43: The woman was wearing biker boots.
2007		T. Dorsey Hurricane Punch 64: They have excellent biker rallies.
2015		S. King Finders Keepers (2016) 168: He might not yet be able to grow the biker moustache he saw in his dreams, but he had balls as well as smarts.
2022		I. Fitzgerald Dirtbag, Massachusetts 83: A legendary biker bar.

4. a ‘biker movie’, devoted to the fictionalized exploits of outlaw motorcyclists.

1987

‘Joe Bob Briggs’ Joe Bob Goes to the Drive-In 61: Hell’s Angels on Wheels (1967): Some say it’s the best of the bikers.