Denshi Jisho — Online Japanese dictionary

ねんね bed-time (for a baby); going bye-byes
Noun, Suru verb 
年々 ねんねん years; year by year; annually; considering his age
Common word, Adverbial noun, Temporal noun 
年年 ねんねん years; year by year; annually; considering his age
Adverbial noun, Temporal noun 
念々 ねんねん continually thinking about something
Noun 
念念 ねんねん continually thinking about something
Noun 
年々歳々 ねんねんさいさい annually; every year; year in year out; from year to year
Adverb, Noun 
年年歳歳 ねんねんさいさい annually; every year; year in year out; from year to year
Adverb, Noun 

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