adverb
1.
a. : once and once more
spoke to her once and again
b. : two or more times
have heard it said once and again
2. : now and again : from time to time : occasionally , sometimes
once and again this sort of thing will happen
adverb
1.
a. : once and once more
spoke to her once and again
b. : two or more times
have heard it said once and again
2. : now and again : from time to time : occasionally , sometimes
once and again this sort of thing will happen
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012