Green’s Dictionary of Slang

1. (US) an old-fashioned person.

1884		Life 4 200/1: The Bum-Bum drinketh the brine from the sea, / And the waybacker bloweth out the gas!
1890		E. Custer Following the Guidon 261: We were, in Western terms, ‘waybacks from wayback.’.
1915		M.G. Hayden ‘Terms Of Disparagement’ in DN IV:iii 210: way-back, one who is old fashioned.

2. (Aus./N.Z./US) the outback or the West or any rural nowhere.

1884		Boston Globe Oct. n.p.: His unkempt hair, gawky appearance, and homespun suit [...] all bespoke the citizen from wayback [DA].
1889		Hamilton Spectator (Vic.) 1 Jan. 4/1: [B]ronzed and bearded visitors from the way-back who have come to Melbourne to be robbed.
1890		E. Custer Following the Guidon 261: We were, in Western terms, ‘waybacks from wayback.’.
1900		Bulletin (Sydney) 6 Jan. 12/4: An intermittent affliction descended upon Melbourne […] in the person of an old man from wayback who wants twenty pounds for a horse with ingrowing hoofs. [Ibid.] 10 Mar. 14/2: When travelling way-back an old woman came out of a house to meet me. She told me she was living alone, and had not seen anyone for weeks.
1908		Sun. Times (Perth) 1 Nov. 45/3: The administration of the Royal Agricultural Society’s last annual circus, as many visitors from Way Back critically styled it, left much to be desired .
1914		Morn. Bulletin (Rockhampton, Qld) 11 Aug. 10/1: Incidents in the ‘Wayback’. A successful bush missionary requires to be a man of many callings.
1936		‘F. Gerald’ Millionaire in Memories 106: Blackall was much the same as any other township ‘way back’ [OED].
2003		McGill Reed Dict. of N.Z. Sl. 227: wayback A remote rural district. ANZ late C19.

3. (also waybacker) a person or animal from the outback.

1890		Bathurst Free Press (NSW) 12 July 2/6: [T]he ball was never in the ‘waybacks’ territory for more than a quarter of a minute at a time.
1890		Bathurst Free Press (NSW) 15 Nov. 6/2: People who carefully fold up their napkin after dining table d’hote are usually ‘way backers’ .
1900		Sun. Times (Sydney) 2 Dec. 6/8: The Wayback Family. Mr. and Mrs. Wayback and family, from Dingo Flat, beyond the Wallaby Ranges, have come to town to witness the Commonwealth celebrations.
1904		Sun. Times (Perth) 6 Mar. 10/2: They prowl around [...] keeping a sharp eye out for the unsophisticated waybacker who rolls in with his swag from the bush.
1906		in Kansas Hist. Society IX 516: When we drove into Olathe we must have looked liked ‘way-backers’ [DA].
1910		Bulletin (Sydney) 4 Aug. 14/4: Newchum: ‘Are those the big mosquitoes I hear so much about?’ / Wayback: ‘No, them’s just plain crows.’.
1915		Barrier Miner (Broken Hills, NSW) 4 Feb.8/4: He was a wayback himself.
1918		Sth Bourke & Mornington Jrnl (Vic.) 4 Apr. 4/1: ‘What is this?’ inquired the waybacker.
1919		C.H. Thorp Handful of Ausseys 199: Yer wayback, silly blanker [...] that bloke’s wax.
1924		G.H. Lawson Dict. of Aus. Words And Terms 🌐 WAYBACK — An Australian resident living far removed from townships and not versed in city customs.
1931		Western Mail (Perth) 15 Oct. 44/5: ‘A Waybacker‘ [...] states he wishes to subscribe to the ‘Western Mail’.
1936		‘Banjo’ Paterson Shearer’s Colt 7: These way-backers will come at anything if you pitch the tale strong enough.

4. in attrib. use of sense 3.

1901		Sydney Sportsman (Surry Hills, NSW) 2 Jan. 1/1: One or two welshers glt in some fine work on the wayback flats.
1903		Barrier Miner (Broken Hills, NSW) 29 July 3/4: After the race the wayback punter was seen in a secluded corner of the enclosure.
1915		Register (Adelaide) 24 May 3/4: ‘Wayback Teachers‘ [...] The Minister will sanction no appointment of teachers to ‘way-back’ schools who are not at least 20 years of age.
1924		Worker (Brisbane) 24 Apr. 10/5: Brightening Wayback Life [...] the Commonwealth Railway Commissioner has provided a travelling picture show.

5. (US black) an old person.

1971

(con. 1930s) D. Wells Night People 67: I saw a little ‘way-back’ hit on you.