Nouns

(n)tacklethe person who plays offensive or defensive tackle on a football team“the right tackle is a straight A student”
(n)rigging, tacklegear consisting of ropes etc. supporting a ship's masts and sails
(n)tackle(American football) a position on the line of scrimmage, typically opposite one of the offensive guards“it takes a big man to play tackle”
(n)tackle(American football) grasping an opposing player with the intention of stopping by throwing to the ground

Verbs

(v)undertake, tackle, take onaccept as a challenge“I'll tackle this difficult task”
(v)harness, tackleput a harness“harness the horse”
(v)tackleseize and throw down an opponent player, who usually carries the ball