1) the act of founding, establishing, building etc
1a) the act of creating, creation
1b) creation, i.e. thing created
1b1) of individual things, beings, a creature, a creation
1b1a) anything created
1b1b) after a rabbinical usage (by which a man converted from idolatry to Judaism was called)
1b1c) the sum or aggregate of things created
1c) institution, ordinance
Part of Speech: noun feminine
Citing in TDNT: 3:1000, 481
From G2936; original formation (properly the act; by implication the thing, literally or figuratively): - building, creation, creature, ordinance.
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 κτίσις; click on the second column to search for that grammatical form of the root κτίσις; click on the third column to search for that word and grammatical form; click on the total to search for the root κτίσις.