Metapod

The English Metapod is built from joining metamorphosis and pod.

We'll start with pod as that describes the current state in the evolution - namely that Caterpie has evolved into a cocoon. This is further emphasised by the fact Metapod is called a Cocoon Pokémon in the official Pokédex entry.

Metamorphosis on the other hand refers to a transformation. The dictionary definition describes a metamorphosis, in biological terms, as a profound change in form from one stage to the next in the life history of an organism. It further describes it as any complete change in appearance, character, circumstances, etc.

The Japanese name for Metapod is written in Katakana as トランセル (toranseru) which can also be translated to Hiragana as とらんせる.

I'll admit that the Japanese name for Metapod has me a bit stumped.

I took the English words as a cue but metamorphosis in Japanese is へんしん (henshin; Kanji 変身) while "to transform" is かえる (kaeru; Kanji 変える). Meanwhile, cocoon in Japanese is まゆ (mayu; Kanji 繭). None of these fit into either the Hiragana (とらんせる) or Katakana (トランセル) spelling for Metapod.

Time for a little detour into Trademarked Romaji. Every Pokémon has a "trademarked romaji" name which differs ever so slightly from their Kana spelling. In Metapod's case the Kana name トランセル (toranseru) has the Trademark Romaji of transel. The Trademark Names are the romaji form as written on the trademark filing. Some Pokémon name meanings need to use the Kana to fully appreciate the subtleties behind the name, while others (as I believe to be the case with Metapod) are based very heavily on English words. As such the names should not be read as if in Japanese (e.g. toranseru) but instead as if the word were English (e.g. transel - which could never be written that way in normal Japanese).

So with that in mind, I feel the Japanese name is meant to be similar to the English and is a combination of transform (aka metamorphosis) and cell (aka pod or cocoon).

And this is exactly what is taking place with Metapod right now as it wraps itself in a cocoon to begin the transformation from a Caterpie into something completely different. But what could Caterpie be evolving into?