snap has 34 distinct synonyms spread across 18 of its 26 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.
the act of catching an object with the hands
“Mays made the catch with his back to the plate”
a spell of cold weather
“a cold snap in the middle of May”
tender green beans without strings that easily snap into sections
a crisp round cookie flavored with ginger
the noise produced by the rapid movement of a finger from the tip to the base of the thumb on the same hand
“servants appeared at the snap of his fingers”
the tendency of a body to return to its original shape after it has been stretched or compressed
“the waistband had lost its snap”
an informal photograph; usually made with a small hand-held camera
“my snapshots haven't been developed yet”
a fastener used on clothing; fastens with a snapping sound
“children can manage snaps better than buttons”
any undertaking that is easy to do
“marketing this product will be no picnic”
the act of snapping the fingers; movement of a finger from the tip to the base of the thumb on the same hand
“he gave his fingers a snap”
Synonyms, antonyms and the broader and narrower relations for snap come from Princeton University’s WordNet. Full sources and licences.
close with a snapping motion
“The lock snapped shut”
move with a snapping sound
“bullets snapped past us”
put in play with a snap
“snap a football”
lose control of one's emotions
“When she heard that she had not passed the exam, she lost it completely”
bring the jaws together
“he snapped indignantly”