(きおく)(ちが)

きおくちがい
noun
faulty memory; misremembering
1. faulty memory; misremembering
remembering something incorrectly; a mistaken recollection
それは(わたし)記憶(きおく)(ちが)いだった。
That was my misremembering.
約束(やくそく)()記憶(きおく)(ちが)いしていた。
I had misremembered the date of the appointment.
(かれ)名前(なまえ)記憶(きおく)(ちが)いでなければ田中(たなか)さんだったはずだ。
If I'm not misremembering, his name should have been Tanaka.

Composed of 記憶(きおく) (memory) + (ちが)い (difference/mistake). Specifically means remembering facts incorrectly — the memory itself is wrong, not that you forgot.

COMMON PATTERNS:

  • 記憶(きおく)(ちが)いだった: it was a faulty memory
  • 記憶(きおく)(ちが)いでなければ: if I'm not misremembering
  • 記憶(きおく)(ちが)いをする: to misremember

SIMILAR WORDS:

  • 勘違(かんちが)い: misunderstanding, misconception (broader — covers misunderstanding in general)
  • (おも)(ちが)い: mistaken thought, wrong assumption
  • (わす)れ: sudden memory lapse (tip-of-the-tongue — you know it but can't recall)
  • 物忘(ものわす)れ: forgetfulness (general tendency, often associated with aging)

NUANCE:
記憶(きおく)(ちが)い is relatively neutral and non-blaming. It acknowledges that memory can be unreliable without implying negligence.