From apollymi (G622, to destroy utterly), denoting ruin, destruction, waste, or loss. It describes both the process and the state of being destroyed — physical ruin, spiritual perdition, and the eschatological fate of the condemned. Notably, it is also used for the 'waste' of expensive ointment poured on Jesus (Matt 26:8).
This word marks the terrible alternative to salvation. Jesus taught that the 'broad way' leads to apōleia — destruction (Matt 7:13). Paul describes enemies of the cross whose 'end is destruction' (Phil 3:19). Peter warns of false teachers who bring in 'destructive heresies' (2 Pet 2:1) and face the same apōleia they peddle. Judas is called 'the son of perdition' (John 17:12), as is the man of lawlessness (2 Thess 2:3). Yet the ointment episode (Matt 26:8) reveals an irony: what the disciples call 'waste' Jesus calls beautiful worship. The world's economy calls extravagant devotion destruction; God's economy calls stinginess toward Christ the true apōleia. The word forces a choice: which kind of loss are you willing to accept?