loft has 3 distinct synonyms spread across 2 of its 8 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.
floor consisting of a large unpartitioned space over a factory or warehouse or other commercial space
Synonyms, antonyms and the broader and narrower relations for loft come from Princeton University’s WordNet. Full sources and licences.
(golf) the backward slant on the head of some golf clubs that is designed to drive the ball high in the air
propel through the air
“The rocket lofted the space shuttle into the air”
kick or strike high in the air
“loft a ball”
lay out a full-scale working drawing of the lines of a vessel's hull