Workhorse rhymes with:
clotheshorse, deadhorse, racehorse, whitehorse, agresource, clotheshorse, concourse, counterforce, deadhorse, healthsource, intercourse, racehorse, taskforce, telsource, uniforce, unisource, whitehorse, wilberforce, workforce
Workhorse sounds like:
weyerhaeuser's, worker's, workers, workers', workhorses