Does 华裔 mean 'overseas Chinese'? Is 华裔 a term that means an ethnically Chinese person born and raised abroad? What about 2nd generation? Does it apply to, say, American born Chinese, Chinese-Canadians, Chinese-Australians, Chinese-Singaporeans, Chinese-Vietnamese etc?

It obviously does not apply to Chinese born and raised in mainland China. But does this term apply to people born and raised in Taiwan, Hong Kong and Macau? 

Or let's say you are a Uyghur 维吾尔族 living overseas - do you identify as 华裔 Or 华人?

Maybe depends on political view and not the etymology of the word...

Also, how is 华裔 different from 华侨 or even 华人?
华裔：华夏族的后裔，但大多数指华侨在侨居国所生并取得侨居国国籍的子女

华侨：尚未加入外籍的中国公民，但长期居于国外；包括已取得居住国永久居民身份者，仍保留本国公民身份

华人：属于中华民族的人的泛称

华人： All Chinese

华侨： Chinese Live overseas but no citizenship

华裔： 华侨's children, get the citizenship

Taiwanese, Hongkongese, Macanese, called 同胞

Uyghur living overseas, you can call him 华人, if you dont know his identity.