A soldier mounted on horseback WordNet 3.0 & Open English WordNet

Trooper from the French "troupier" is the equivalent rank to private in a regiment with a cavalry tradition in the British Army and many other Commonwealth armies, including those of Australia, Canada, South Africa and New Zealand; it is also used by the Irish Army. Wikipedia

A military private rank Wikipedia Disambiguation

Military rank, typical to cavalry in British and Commonwealth armies Wikidata

A soldier in the cavalry. Wiktionary