load has 21 distinct synonyms spread across 9 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. 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 quantity that can be processed or transported at one time
“the system broke down under excessive loads”
goods carried by a large vehicle
an amount of alcohol sufficient to intoxicate
“he got a load on and started a brawl”
the power output of a generator or power plant
an onerous or difficult concern
“the burden of responsibility”
a deposit of valuable ore occurring within definite boundaries separating it from surrounding rocks
the front part of a guided missile or rocket or torpedo that carries the nuclear or explosive charge or the chemical or biological agents
electrical device to which electrical power is delivered
transfer from a storage device to a computer's memory
put (something) on a structure or conveyance
“load the bags onto the trucks”
corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones
“adulterate liquor”
Synonyms, antonyms and the broader and narrower relations for load come from Princeton University’s WordNet. Full sources and licences.