Medetai: 2 Different Meanings of the Japanese Word
With positive meanings, Medetai (めでたい) reminds many Japanese of red sea bream, as in its word, Tai (たい) can mean sea bream or 鯛 (Tai).
The truth is that Medetai is derived from Mede-Itashi (愛で甚し) and is unrelated to fish.
But Taiyaki pancake got its idea from Medetai, and many people associate the word with a fish.
Meaning of Medetai (めでたい)
Medetai originally means: so good (excellent or splendid), like no choice but to admire. But its contemporary meaning is often: auspicious or happy or good news, like
- めでたい日 (Auspicious day)
- めでたい色 (Happy color)
- それはめでたい (that is Good News)
In the Japanese language, the prefix お (O) can be an honorific. And you can use Medetai and Omedetai interchangeably, like
- おめでたい日 (Auspicious day)
- おめでたい色 (Happy color)
- それはおめでたい (that is Good News)
In many cases, we use Omedetai in the same way as Medetai. But the former can have a sarcastic connotation (like naive or easily deceived) with a person, so be cautious.
- 君はおめでたいね (implicitly meaning: you are Naive)
- おめでたい人 (in other words, 世間知らずな人 or Naive person)
(Reference Page: Goo Japanese Dictionary めでたい )