Infantry which is transported on mounts (e.g. horses) but fights on foot.(noun)
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Use "mounted infantry" in a sentence
"A short while later a rapid advance by tanks and mounted infantry resulted in the capture of the undamaged Susha road bridge."
"Soviet tanks and mounted infantry were advancing along the Suyevo-Judino ridge toward the Pskov-Ostrov rail line."
"Oblensky was as ambitious as the next Red Army Colonel, and delighted at the opportunity to demonstrate the superiority of mounted infantry in pursuit."