Ghẹ refers to swimming crabs (portunidae) – crabs that have hind legs that are flattened to form swimming paddles. Well-known ghẹ include the ghẹ xanh (portunus pelagicus, the blue swimmer), the ghẹ dĩa or ghẹ đỏ (portunus haanii, the red warty swimming crab), and the ghẹ chấm (portunus trituberculatus). Note that not all crabs with swimming paddles are called ghẹ – a crab must live in the ocean or estuaries and have the characteristic angular carapace and long, narrow claws (chelae) to be called con ghẹ. The mud crabs scylla serrata (cua bùn) and scylla paramamosain (cua xanh) are called cua because they live in fresh water, their claws are large, and their carapaces are rounder.

There are other Việt words for specific kinds of crabs, including rạm or đam (varunidae), dã tràng (sand bubbler crabs), cáy (ocypodidae), cà ra (Chinese mitten crabs), and cúm núm (calappidae, from cua khúm núm, due to the way they appear to hide their faces – Google Translate amusingly renders “cúm núm” as “nipple flu” in English). Like ghẹ, these aren’t strict taxonomic or phylogenetic classifications – they’re common names based on appearance (morphology) and habitat.

Ghệ or ghẹ can also be used informally to refer to women, as in “ghẹ mới của tao” (my new girlfriend), but this is a little vulgar and should be avoided in polite company.

The French title means “Knights of the Sky” which, besides sounding a lot classier, has completely different connotations. You see, when we think of knights, we think of honour, chivalry and adventure; when we think of fighters on the other hand, we just think of, well, fighting…

One thing about the whole phenomenon has started to annoy me, and that’s the name that anime geeks have given them. They call them “neko mimi” and write it “猫耳”. Now these two characters mean “cat” and “ear” respectively, and the native Japanese readings (kun-yomi) are “neko” and “mimi”.

But if you see two ideographic (kanji) characters jammed together like that, you don’t use the native Japanese readings. You use the Chinese-derived readings (on-yomi). For example, “少女” (young girl) is read always as “shou jo” and never as “suko onna”. On the other hand, “少し女” (notice the conjunction) is read as “suko shi onna”.

Likewise, “猫耳” should be read as “byou ji” (although no-one would ever say that), and “猫の耳” should be read as “neko no mimi” (note the conjunction).

Now there are other cases where people want to use the native Japanese reading for several characters in a row with no conjunctions, such as the company Kuro Neko Yamato (roughly Yamato the Black Cat). But they make the desired pronunciation obvious by writing their name in phonetics (katakana), as “クロネコヤマト” rather than the ideographics “黒猫大和” (which should be pronounced “ji byou dai wa” or maybe “ji byou yamato”).

“Neko mimi” should be written in phonetics (i.e. as “ネコミミ”), or else catgirls should be called “byou ji”!