golyplot wrote:I remembered that ちゃった is an abbreviation of shimatta (meaning "happened unfortunately") from going through Erin's challenge. However, I wasn't confident about it, so I looked it up in ichi.moe anyway. Much to my surprise, ichi.moe got it wrong, listing the meaning as the lesser used alternate meaning "indicates completion (to finish ...)" instead. Or am I the one wrong here?
Incidentally, I also noticed Noriko say what sounded like "hamachatta" when talking about the show Snowpiercer, presumably meaning that she has unfortunately been addicted to it lately, a combination of ちゃった and はまる (to be addicted).
Originally, しまう, which was written しまふ before Japanese orthography was reformed, did indeed have the meaning of "to finish."
From 旺文社 全訳古語辞典 under 仕舞ふ: "し終える。始末する。"
In linguistics, there's a concept called grammaticization (or grammaticalization or grammatization...) whereby words lose their core meaning and adopt grammatical functions or pragmatic meanings. A great example of this is the word "will", which originally meant "to want". It went through a period where it lost its core meaning and just came to denote someone's intention (e.g. I will go tomorrow) and finally came to denote the future (e.g. It will rain tomorrow). A common feature of grammaticized words is that they are given shortened forms (e.g. "He
'll be late).
仕舞ふ has gone through a similar process, but ended up with a pragmatic (i.e. emotive) meaning. In many cases, しまう simply denotes the speaker's stance regarding the action in question. This stance is most often somewhat negative, expressing some form of regret (e.g. 花子行っちゃったね) or embarrassment, but can also sometimes put a somewhat silly spin on those emotions (ふふ、冷蔵庫のビール飲んじゃった [a very てへぺろ moment, indeed]). As with any grammaticized word, it comes with shortened forms, of which there are a few: ちゃう (a bit more neutral/feminine), ちまう (masculine), ちった (cutesy and only used in the past form as far as I’m aware). 大辞林 has this to say about しまう: "動詞の連用形に助動「て(で)」を添えた形について、その動作がすっかり終わる、その状態が完成することを表す。
終わったことを強調したり、不本意である、困ったことになった、などの気持ちを添えたりすることもある。" (Attaches to the continuative form a verb followed by the auxiliary ‘te (de)’ and expresses that the action has finished entirely or that the state has come to an end.
It can also emphasize the completion of an action or convey the feeling that it was unintended or has created an awkward situation.)
While it certainly does still have a meaning of doing something to completion, I would say that the pragmatic meaning is more dominant in many cases based on my Japanese linguistics classes and on my own experience. I am, however, by no means an expert.