Refers to the act of saving people or vessels in distress, especially in maritime or disaster contexts. Often used in compound nouns.
The Japan Coast Guard's rescue operation was swift.
A distress signal was sent from the ship in distress.
search and rescue aircraft; rescue plane
rescue ship; salvage boat
search and rescue; SAR
distress signal; SOS
lifebuoy
rescue helicopter
Compound of 救 (save, rescue) and 難 (difficulty, distress). The combination directly conveys rescuing from a difficult or dangerous situation.