长年累月

長年累月
chángniánlěiyuè
  1. year in, year out (idiom)
  2. (over) many years

CEDICT

over many years and months; year in, year out

Wiktionary

极言很长的一段时间。

重編國語辭典

极言很长的一段时间

維基詞典

Entry Composition

1 长年 chángnián all the year round
2 累 lěi
  1. to accumulate
  2. to involve or implicate (Taiwan pr. lèi)
  3. continuous
  4. repeated
3 月 yuè
  1. moon
  2. month
  3. monthly

classifiers: 個, 輪

Related entries

成年累月 chéngniánlěiyuè year in, year out (idiom)
积年累月 jīniánlěiyuè
  1. year in, year out (idiom)
  2. (over) many years
整年累月 zhěngniánlěiyuè
  1. month after month, year after year
  2. year in, year out
多年 duōnián
  1. many years
  2. for many years
  3. longstanding
湯姆去世多年了。

Tom has been gone for ages.

Source: Tatoeba

数年 shùnián
  1. several years
  2. many years
數年過去了。

Several years went by.

Source: Tatoeba