Anything having to do with a physical object. Guns are not tactical. Clothing is not tactical.
Thoughts and methods referring to specific, well, tactics, are tactical. Thus the adjective form of the word.
You can have a tactical strike.
A tactical mindset (if your mind is thinking with tact all the time).
You cannot have a tactical AR-15. It just doesn't work that way. You can have an AR-15 which has additions that make the tactical PLAN easier to implement - blinding lights and such - but these alone are not tactical.
Is it just me, or has anyone else noticed that LA Police Gear is disproportionately represented here? Not to put them down,... just bought wifey a streamlight stinger Led when they were haveing a shipping sale a month or so ago.