1) empty, braggart talk
2) an insolent and empty assurance, which trusts in its own power and resources and shamefully despises and violates divine laws and human rights
3) an impious and empty presumption which trusts in the stability of earthy things
Part of Speech: noun feminine
Citing in TDNT: 1:226, 36
From G213; braggadocio, that is, (by implication) self confidence: - boasting, pride.
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 ἀλαζονεία; click on the second column to search for that grammatical form of the root ἀλαζονεία; click on the third column to search for that word and grammatical form; click on the total to search for the root ἀλαζονεία.