Wild: 狂热的，野生的；goose：鹅；chase： 追逐，追赶；
字面来看，wild goose chase是野生的鹅的追逐，那实际是什么意思呢？
In English: Pursuing something that seems to be pointless or unattainable.意思就是说：追逐一些无意义或者很难办到的事情；
It's believed that this phrase's origin is rooted in some type of 16th century horse racing.
传说这个slang的来源与16世纪的赛马比赛有关。a horse race in which the lead rider would be pursued by other riders, which is said to be similar to how geese flying in a formation will follow the one in the lead.
在赛马时，跑在最前面的马会被其他马追赶，这和鹅群追赶跑在最前面的鹅一样。追赶领跑者，很有可能因为追不上而失败，那么就用wild goose chase指代徒劳无益的追求。
His scheme of being a movie star is a wild-goose chase.
I was searching for my cat all over the house but I couldn't find her anymore, it really felt like I was on a wild goose chase. It turned out my cat was outside during the entirety of my search, no wonder I couldn't find her!