also: さいやく
noun
corvée labor system (ritsuryō)
Historical term referring to the mandatory labor obligation for able-bodied men under the ritsuryō legal codes, typically involving work in the capital.
律令制下では、成年男子に歳役が課せられていた。
Under the ritsuryō system, adult men were subject to the corvée labor obligation.
From 歳 (sai, 'year') + 役 (eki, 'service/labor'), referring to the annual labor duty. The reading さいやく is a variant.