Just about anything used for fishing can be called tackle.
I know there are 'tackle boxes'.  I use them for my jewelry findings and beads.
Well a fishing rig is the completed assembly of tackle.
So, is tackle like line, lures, weights and . . .?
Also sinkers, floats, rods, reels, baits, lures, spears, nets, gaffs, traps, waders, etc...
So, why do they call it 'tackle'?
The term "tackle" has been in use since 1398.
What does 'tackle' mean; or better, where it did it originate?