side has 6 distinct synonyms spread across 5 of its 14 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. Its 2 recorded opposites are top, bottom.
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.
Synonyms, antonyms and the broader and narrower relations for side come from Princeton University’s WordNet. Full sources and licences.
one of two or more contesting groups
“the Confederate side was prepared to attack”
either the left or right half of a body
“he had a pain in his side”
a line segment forming part of the perimeter of a plane figure
“the hypotenuse of a right triangle is always the longest side”
a family line of descent
“he gets his brains from his father's side”
a lengthwise dressed half of an animal's carcass used for food
an elevated geological formation
“he climbed the steep slope”