lastdefense
nounUK /ˌlɑːst dɪˈfens/
US /ˌlæst dɪˈfens/
The very last thing that keeps you safe when everything else is gone.
The castle wall was the town's last defense against the storm.
RELATED WORDS
OTHER MEANINGS
2. The final player or position that stops the other team from scoring.
The goalie is the team's last defense.
3. The last argument or reason someone uses when all others fail.
Honesty was his last defense when the questions got hard.
4. The final part of a system that keeps something from breaking.
The backup battery is the last defense for the alarm.