to step or walk on or over, to beat or press with the feet, or execute through stepping or dancing;
e.g. We treaded onward to the castle, but it was a long and grueling walk.
(verb)
to copulate with - used in connection with a male bird;
e.g. The bluejay tread forward in a game of courting his female target.
(noun)
the part of a wheel or tire that makes contact with a road or rail or the grooves cut into the tire, the imprint on the bottom of a shoe, or the upper horizontal part of a step;
e.g. He did not need to measure the tread since he could see that his tires were bald.