also: きゃくねん
noun, adverb
Rare, literary, or formal term for 'last year'; in modern Japanese, 去年 (きょねん) is the standard word.
客年の業績を振り返る。
We review last year's performance.
客年は記録的な猛暑だった。
Last year was a record-breaking heat wave.
The kanji 客 (guest, visitor) and 年 (year) combine to mean 'the year that has passed as a guest', i.e., last year. The exact historical derivation is uncertain, but the spelling is conventionally associated with this meaning.