time has 8 distinct synonyms spread across 6 of its 15 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
a period of time considered as a resource under your control and sufficient to accomplish something
“take time to smell the roses”
an indefinite period (usually marked by specific attributes or activities)
“the time of year for planting”
the continuum of experience in which events pass from the future through the present to the past
“he waited for along time”
a person's experience on a particular occasion
“he had a time holding back the tears”
a reading of a point in time as given by a clock
“do you know what time it is?”
the fourth coordinate that is required (along with three spatial dimensions) to specify a physical event
the period of time a prisoner is imprisoned
“he served a prison term of 15 months”
assign a time for an activity or event
“The candidate carefully timed his appearance at the disaster scene”
set the speed, duration, or execution of
“we time the process to manufacture our cars very precisely”
regulate or set the time of
“time the clock”
adjust so that a force is applied and an action occurs at the desired time
“The good player times his swing so as to hit the ball squarely”
Synonyms, antonyms and the broader and narrower relations for time come from Princeton University’s WordNet. Full sources and licences.