[UK, from rude slang noun nadgers for testicles; compare American & British bollixed] Of software or hardware (not people), to twiddle some object in a hidden manner, generally so that it conforms better to some format. For instance, string printing routines on 8-bit processors often take the string text from the instruction stream, thus a print call looks like jsr print:"Hello world". The print routine has to nadger the saved instruction pointer so that the processor doesn't try to execute the text as instructions when the subroutine returns. See adger.