1650s, "freely bestowed," from Latin gratuitus "done without pay, spontaneous, voluntary," from gratus "pleasing, agreeable," from gratia "favor" (see grace (n.)). Earlier was gratuital (1590s). Sense of "uncalled for, done without good reason" is first recorded 1690s.
gratuitous 英文释义
1. without cause;
"a gratuitous insult"
2. costing nothing;
"complimentary tickets"
3. unnecessary and unwarranted;
"a strikers' tent camp...was burned with needless loss of life"