1) Voice type 
A sopranist (also, sopranista or male soprano) is a male singer who is able to sing in the vocal tessitura of a soprano usually through the use of falsetto vocal production. This voice type is a specific kind of countertenor. In rare cases an adult man may be able to sing in the soprano range using his normal or modal voice and not falsetto due to...
• (n.) A treble singer.
So·pra'nist noun (Mus.) A treble singer. 
A sopranist is a treble singer.