Brain hole

Neologisms pop up so fast in China that it is almost impossible to keep abreast of them.  Furthermore, it is very hard to figure out where many of them come from.  Some of them are undoubtedly borrowed from other languages, but given such a twist that it is difficult to recognize the original source.  Others are just made up by imaginative netizens.  If they are taken up by others and catch on, they become part of contemporary vocabulary.

One that I just heard for the first time last week is nǎodòng 脑洞.  It seems to be a fairly new expression, yet one which is wildly popular (9,250,000 ghits).  This literally means "brain cavity / cave / cavern / burrow / grotto".  Yet, from the contexts in which it occurs, I get the idea that nǎodòng 脑洞 actually means something like "extremely imaginative".

This interpretation is supported by adjectival uses of dòng 洞:  profound; thorough; clear; hollow; having a thorough understanding of the actual situation (as though one were seeing through to the bottom of a deep hole).  Cf. the adverbial meaning of "thoroughly".

The same sense of dòng 洞 may be seen in certain collocations into which it enters:

• dòngchá 洞察 ("see clearly; have an insight")
• dòngchálì 洞察力 ("insight; perspicacity; discernment; intuition")

The whole idea of a "brain hole / cavity / cavern" implying imagination or insight reminds me of the depiction of some sages in myth, legend, art, and history as having a conspicuous protuberance of their skull, especially the forehead.  In my own family, we would refer to such super smart people with large bumps sticking out from their cranium as having an extra compartment to add more space for their enlarged brain.

The "standard" translation of nǎodòng 脑洞 on the internet seems to be "brain hole", which sounds weird to me.  See, for example, this Baidu encyclopedia entry, which explains it as having derived from nǎobǔ 脑补 ("brain extension / supplement").  The latter term is clearly borrowed from Japanese anime, as explained in this nice, little article in the Shenzhen Daily and elsewhere.  As for the precise nyuansu ニュアンス ("nuance") of the relevant Japanese terms, I leave it up to the Japanesewallahs to enlighten us.