1) Asker 2) Enquirer 3) Examiner 4) Head counter 5) Inquisitor 6) Inquisitorial 7) Interrogator 8) Interviewer 9) Paper 10) Pollster 11) Querier 12) Questioner 13) Quizzer 14) Tester 1) Asker 2) Enquirer 3) Querier 4) Questioner 5) Someone who asks a question 6) Speaker 7) Talker 8) Utterer 9) Verbaliser 10) Verbalizer 
• (n.) One who inquires or examines; questioner; investigator.
In·quir'er noun [ Written also enquirer .] One who inquires or examines; questioner; investigator. Locke. « Expert inquirers after truth.» Cowper. 
[n] - someone who asks a question