(Koi no takinobori; “A carp climbing a waterfall”)
Spectacular success in life. A person being as successful in society or career – in “the world” – as a carp that manages to overcome rapids and waterfalls in its swim upstream.
This simple noun phrase begins with the noun 鯉 (koi), “carp.” Next we have the noun 滝 (taki), “waterfall,” compounded with and modifying the verb 登る (noboru) – which is in prenominal form, allowing it to function as a noun itself. This compound noun is connection to the carp through associative particle の (no).
Apparently this saying references a part of the Yellow River in China known as the 竜門 (in Japanese Ryuumon), “Dragon Gate,” and full of rapids and waterfalls. The legend tells of a carp that was able to overcome these challenges and successfully swim upstream, after which it became a dragon and flew off into the heavens.
Today (May 5th) was こどもの日 (kodomo no hi), “Children’s Day.” One of the day’s traditions is for families with children to fly carp streamers known as 鯉のぼり (koinobori), apparently in reference to the above legend. In any case, I dug up this carp-related kotowaza in honor of the day… which our son spent being ill, ironically enough. This story is attributed to the Book of the Later Han (後漢書, in Japanese Gokanjo.)
There’s also an idiom about “eels climbing” (鰻登り, unaginobori), indicating that something is climbing rapidly (i.e. “skyrocketing prices”). Conflating this with the carp’s climb is, of course, an error.
(“Yo no naka ni wa jibun no kodomo ni wa koi no takinobori mitai na shusse wo nozomu oya mo iru kamoshirenai kedo, uchi wa kodomo-tachi ga shiawase nara jimi na seikatsu de mo ii to omou.”)
[“I’m sure there are parents out there in the world who wish for spectacularly successful careers for their children, but for us, I think an unexceptional lifestyle is fine as long as they’re happy.”]