Bulwark
Meaning:
Bulwark means a defensive wall, a rampart or any protection against external danger.
Origin:
The term, dating back to the early 15th Century, came from Middle Dutch bulwerke or Middle High German bolwerc, from bole “plank, tree trunk” + werc “work”. Thus “bole-work,” a construction of logs. It took on the figurative meaning of defence or security from the mid-15th Century.
Example sentences:
Vaccines act as a bulwark against many infectious diseases.
When the leader travels abroad, his guards accompany him as a bulwark against enemy attack.
I got drenched in the rain as I did not have an umbrella or any such bulwark to protect me from the downpour.
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