1) how, in what way
Part of Speech: particle
Adverb from the base of G4226; an interrogitive particle of manner; in what way? (sometimes the question is indirect, how?); also as exclamation, how much!: - how, after (by) what manner (means), that. [Occasionally unexpressed in English.]
These two sites give similar information, with the definition from several dictionaries and statistics on the use of the word.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root πῶς; click on the second column to search for that grammatical form of the root πῶς; click on the third column to search for that word and grammatical form; click on the total to search for the root πῶς.