A blow-fly is a fly, often shiny green or blue, that lays its eggs on dead animals, on meat left out, or sometimes on an open wound. The eggs become maggots, which eat the rotting flesh. Farmers, cooks, and doctors all watch for them. You will also see the spelling blowfly, as one word. They are usually bigger and louder than the small flies on fruit. Though actually, blow here is not wind. Older English used blow for what a fly does when it lays eggs on meat — people said the meat was blown. That is how the fly got the name.

麗蠅（口語常叫綠頭蒼蠅；綠的、藍的都算這一類）