Atezuppou (当てずっぽう – Random Guess)
If you do or say something irresponsible with no basis, you will be told “atezuppou” (当てずっぽう) in Japanese.
当てずっぽう
“Atezuppou” means something like random guess, and it’s used like “Atezuppou na koto wo iuna” (当てずっぽうなことを言うな – Don’t say atezuppo things.)
何の根拠もなしに、いいかげんな事を行うことを、日本語で「当てずっぽう」と言います。
The most acceptable theory about its etymology is that it comes from the term “ate zuiryou” (当て推量), which has come to be used since the Edo period.
この語源として最も有力なものは、江戸時代に使われていた「当て推量」から来ているというものです。
Here “ate” (当て) means “prospect,” and “zuiryou/suiryou” (推量) means “guess.”
「当て」は「見込み」を意味し、「推量」は文字どおり推し量るという意味です。
The theory says that “ate zuiryou” became “atezui” for short, and it became “atezuibou” by personifying (“bou” is a suffix word that is sometimes added to boys’ names), and finally it became “atezuppou.”
「当て推量」が「当推（あてずい）」となり、これが擬人化され「当てずい坊」となり、最終的に「当てずっぽう」になったというわけです。
