天地無用

Japanese

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天地無用

Wikipedia ^ja

Short from 天地(てんち) (tenchi, “top and bottom”) + 入替(いれかえ) (irekae, “replace, swap”) + 無用(むよう) (muyō, “prohibited”), i.e. "swapping top and bottom is prohibited."

(Tokyo) てんち・むよー [téꜜǹchì mùyóó] (Atamadaka + Heiban – [1]+[0])^[1]
(Tokyo) てんちむよー [téꜜǹchì mùyòò] (Atamadaka – [1])^[2]^[3]^[4] incorrectly approximated because the cited dictionary's pitch accent format is noncomplex
IPA^(key): [tẽ̞ɲ̟t͡ɕi mɯ̟jo̞ː]

天(てん)地(ち)無(む)用(よう) • (tenchi muyō)

(dated) Shipping terminology to indicate that a package must not be flipped: this way up, this side up

This phrase is sometimes misinterpreted as "top and bottom do not matter", using the more readily comprehensible interpretation of 無用 as meaning "useless" but leading to the exact opposite intended meaning ("it is okay to flip this package"). In Japanese postal services this phrase has been largely replaced by more comprehensible ones like この面(めん)を上(うえ)に (kono men o ue ni, “this side up”) and 逆(さか)さま厳禁(げんきん) (sakasama genkin, “upside down prohibition”).

^ Yamada, Tadao et al., editors (2011), 新明解国語辞典 [Shin Meikai Kokugo Jiten] (in Japanese), Seventh edition, Tokyo: Sanseidō, →ISBN
^ Matsumura, Akira, editor (2006), 大辞林 [Daijirin] (in Japanese), Third edition, Tokyo: Sanseidō, →ISBN
^ NHK Broadcasting Culture Research Institute, editor (1998), NHK日本語発音アクセント辞典 [NHK Japanese Pronunciation Accent Dictionary] (in Japanese), Tokyo: NHK Publishing, Inc., →ISBN
^ “天地無用”, in 日本国語大辞典 [Nihon Kokugo Daijiten]‎^[1] (in Japanese), 2nd edition, Tokyo: Shogakukan, 2000-2002, released online 2007, →ISBN, concise edition entry available here

“天地無用”, in 漢字ぺディア [Kanjipedia]‎^[2] (in Japanese), The Japan Kanji Aptitude Testing Foundation, 2015–2026