'net-zero' is a modern compound formed from 'net' + 'zero'. 'net' (meaning 'remaining after deductions' or 'final') originates from Old French 'net' (meaning 'clean, clear'), ultimately influenced by Latin 'nitidus' (meaning 'shining, neat'). 'zero' entered English via Italian 'zero', from Medieval Latin 'zephirum', which came from Arabic 'ṣifr' (صِفْر) meaning 'empty' or 'nothing'.

'net-zero' arose in late 20th/early 21st-century English as climate-policy vocabulary combining 'net' (the remainder after accounting for removals and offsets) and 'zero' (nothing). The element 'zero' itself moved into European languages from Arabic 'ṣifr' through Italian and Medieval Latin before becoming the English 'zero'.

Individually, 'zero' originally meant 'nothing' and 'net' meant 'remaining after deductions'; combined in modern usage they evolved to mean 'balanced to zero' specifically in the context of greenhouse gas accounting (i.e., emissions minus removals = 0).