Green’s Dictionary of Slang

(S.Afr.) (orig. milit. use.) to keep going, to ‘tough it out’, to ‘bite the bullet’.

1979		D. Herbstein White Man, We Want to Talk to You 132: The soldiers’ radio request programme after lunch on Saturdays was punctuated with ‘can’t wait to see you’ and ‘vasbyt’ (literally, grit your teeth).
1981		P. Wilhelm At the End of a War 14: Sometimes they listened to the radio, to the messages on ‘Forces Favourites’ all about ‘missing you my darling’ and ‘longing to see you’ and ‘Vasbyt.’.
1996		CyberBraai Lex. at www.matriots.com 🌐 They have also learned that [...] ‘Vasbyt’ is our psychological door to a tougher attitude.
2003		W. & S. Olivier Hiking Trails of S. Afr. 248: The Afrikaans name of the trail, Vasbyt, is variously translated as ‘hang on’, ‘grin and bear it’ and ‘bite the bullet’, and this is just what is required.