1) any tool or implement for preparing a thing
1a) arms used in warfare, weapons
2) an instrument
Part of Speech: noun neuter
Citing in TDNT: 5:292, 702
Probably from the primary word ἕπω hepô(to be busy about); an implement or utensil or tool (literally or figuratively, especially offensive for war): - armour, instrument, weapon.
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 ὅπλον; click on the second column to search for that grammatical form of the root ὅπλον; click on the third column to search for that word and grammatical form; click on the total to search for the root ὅπλον.