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v. Present participle of tread.

n. The act of setting down the foot; a step.

n. That which is trampled down.

n. The act of the cock in copulation.

"Every so often one of them flew back to check on the Magician, who was doing what he called treading water, though it looked exactly like swimming in place."

to tread upon   

rise    riser   

treaded    treades    treading    treads    trod    trodden   

surface    apply    give    pair    copulate    couple    mate    tangency    contact    structural member   

trample    to tread in one's steps(or footsteps)    to tread on one's toes    to tread water    to tread out    to tread awry    rubber tread    to tread under foot    to tread the bounds    to tread down   

trod    trodden    interfere   

tread water    untrod   

copulate    subdue    feather    cover    footstep    action    gait    way    track    path   

Ed    Fed    Fred    Freda    Ged    Head    Jed    Med    Ned    Read   

footstep    stride    gait    tramp    thud    clatter    whisper    knock    beat    pace