Agnostic

Part of speech: noun (n.)

One who professes ignorance, or denies that we have any knowledge, save of phenomena; one who supports agnosticism, neither affirming nor denying the existence of a personal Deity, a future life, etc.

Part of speech: adjective (a.)

Professing ignorance; involving no dogmatic; pertaining to or involving agnosticism. -- Ag*nos"tic*al*ly, adv.