[seiji]

It's largely a UK/US-ism I think. It's inappropriate in not-America to say you're male. "Male" just means you're an animal with dangly bits.

US doctor: "A 24 year old male presents with..."

UK doctor: "A 24 year old man presents with..."

[r0h1n]

Here's the Cambridge dictionary on the word: http://dictionary.cambridge.org/us/dictionary/british/male_3

Note the example: "Among the bodies are two unidentified British males."