Deoxythymidine, wanda kuma aka sani da thymidine, kwayoyin halitta ne na nucleoside wanda ya ƙunshi thymine tushe na nitrogen da deoxyribose sugar. Yana daya daga cikin tubalan ginin DNA kuma yana da hannu wajen kwafi da rubuta bayanan kwayoyin halitta. Kalmar “deoxy” tana nufin rashin atom ɗin iskar oxygen a cikin ƙwayar sukari, wanda ke bambanta shi da ƙwayar ribothymidine mai alaƙa, wanda ke ɗauke da sukarin ribose maimakon.