tick

a light rhythmic audible tap or beat; also : a series of such ticks

the time taken by the tick of a clock : moment

a small spot or mark; especially : one used to direct attention to something, to check an item on a list, or to represent a point on a scale

to make the sound of a tick or a series of ticks

to operate as a functioning mechanism : run

to mark with a written tick : check —usually used with off

any of a superfamily (Ixodoidea) of bloodsucking acarid arachnids that are larger than the related mites, attach themselves to warm-blooded vertebrates to feed, and include important vectors of infectious diseases

any of various usually wingless parasitic dipteran flies