t has 10 distinct synonyms spread across 5 of its 6 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 base found in DNA (but not in RNA) and derived from pyrimidine; pairs with adenine
one of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)
a unit of weight equivalent to 1000 kilograms
the 20th letter of the Roman alphabet
thyroid hormone similar to thyroxine but with one less iodine atom per molecule and produced in smaller quantity; exerts the same biological effects as thyroxine but is more potent and briefer
hormone produced by the thyroid glands to regulate metabolism by controlling the rate of oxidation in cells
“thyroxine is 65% iodine”
Synonyms, antonyms and the broader and narrower relations for t come from Princeton University’s WordNet. Full sources and licences.