1.
same year, same class, same cohort
People who entered a company, school, or organization in the same year. An important concept in Japanese workplace culture, where cohort bonds are strong.
彼は同期の中で一番優秀だ。
He is the most talented among those who joined the same year.
同期の仲間と飲みに行った。
I went drinking with colleagues from the same cohort.
入社同期は三十人いたが、今も残っているのは半分だけだ。
There were thirty people in my cohort when we joined the company, but only half remain now.
2.
synchronization
Aligning the timing or data of two or more systems. Used in computing, engineering, and telecommunications.
データを同期する。
To synchronize data.
スマホとパソコンの同期がうまくいかない。
The synchronization between my smartphone and computer isn't working well.
クラウドと自動同期される設定にしてある。
It's set to automatically sync with the cloud.
USAGE:
Sense 1 is central to Japanese workplace culture. 同期 bonds are often lifelong, and colleagues from the same hiring year form a natural support network. Can be used as a noun modifier: 同期の桜 (lit. "cherry blossoms of the same year" — comrades who share the same fate).
Sense 2 is the technical meaning used in IT and engineering.
COMMON COLLOCATIONS:
- 同期の仲間: cohort members, colleagues from the same year
- 入社同期: same-year company entrants
- データを同期する: to sync data
- 自動同期: automatic synchronization