蝦 is shrimp, and 餃 is dumpling, so 蝦餃 is shrimp dumpling.
Steamed bonnet-shaped shrimp dumplings, encased in a thin, pleated (typically twelve pleats), translucent skin (these are often called crystal shrimp dumplings). This dish, along with siu mai, is a hallmark of Cantonese dim sum (and so are the servers in dim sum restaurants pushing the carts and announcing “hā gáau, sīu maaih“)
Pronunciation
The name of this dish is typically written in English as har gow, but like many English spellings of Chinese pronunciation (in this case, Cantonese), it's a bit off. There's no “r“ sound, so it's more like laughing “haw haw“ instead of “har har.“