失念（しつねん、shitsunen）
- forgetfulness

The Japanese word 失念 しつねん means "to forget," "to be remiss," or "to fail to remember." It implies a lapse in memory or a failure to recall something that should have been remembered. This can range from forgetting a minor detail to overlooking a crucial piece of information. The word often carries a polite or formal tone. The act of 失念 usually implies that someone has an awareness that they should have remembered something, but they did not.

⚫︎会議の時間を失念していました。 Translation: I had forgotten the time of the meeting. ⚫︎約束を失念してしまい、大変申し訳ございません。 Translation: I am very sorry; I forgot about the appointment. ⚫︎書類を提出することを失念していた。 Translation: I had forgotten to submit the documents.

⚫︎失念 is commonly used in both written and spoken Japanese. ⚫︎It's considered a polite and formal way to express forgetting something. ⚫︎It's often used in situations where you need to apologize for forgetting something. ⚫︎It is especially useful in business settings or when addressing someone of higher status. ⚫︎You might use it when talking about an important deadline or appointment you forgot about. ⚫︎When using 失念, you're usually acknowledging your mistake or shortcoming.

⚫︎失念 is written using the kanji 失 (しつ, meaning "loss" or "failure") and 念 (ねん, meaning "thought," "idea," or "mind"). ⚫︎The reading is しつねん (shitsunen). ⚫︎It's almost always written in kanji.

⚫︎忘れる (wasureru): This is the most common and general word for "to forget." ⚫︎忘却 (boukyaku): Meaning “oblivion”, this word is more formal and refers to the act of forgetting. ⚫︎うっかり忘れる (ukkari wasureru): "To forget carelessly." ⚫︎ど忘れする (do wasuresuru): "To completely forget" or "To blank out". ⚫︎思い出せない (omoide senai): "Cannot remember". ⚫︎忘れがち (wasuregachi): "Tends to forget".

⚫︎覚えている (oboete iru): To remember. ⚫︎記憶する (kioku suru): To memorize, to remember.

メールを返信することを失念しておりました。大変失礼いたしました。 ・Translation: I had forgotten to reply to the email. I am very sorry. ・Explanation: This sentence demonstrates a formal apology for forgetting to reply to an email. The speaker acknowledges their mistake with the polite expression 失念 and apologizes for the oversight.

重要な書類をコピーすることを失念し、会議に遅刻しました。 ・Translation: I forgot to copy the important documents, and I was late for the meeting. ・Explanation: This sentence explains that due to [失念], the speaker was late for the meeting. It highlights the consequence of forgetting something important.

⚫︎The word 失念 is formed by combining the kanji 失 (shitsu), meaning "to lose" or "to fail", and 念 (nen), meaning "thought," "idea," or "mind." ⚫︎Therefore, the word literally means "to lose thought" or "to lose from one's mind," which directly reflects its meaning of "to forget."