I'm not sure what is the correct definition of genocide these days, but that seems like a semantic point. Here is a quote from de Las Casas you can describe it in whatever terms seem appropriate to you:
“They [Spanish explorers] forced their way into native settlements, slaughtering everyone they found there, including small children, old men, pregnant women, and even women who had just given birth. They hacked them to pieces, slicing open their bellies with their swords as though they were so many sheep herded into a pen. They even laid wagers on whether they could slice a man in two at a stroke, or cut an individual’s head from his body, or disembowel him with a single blow of their axes. They grabbed suckling infants by the feet and, ripping them from their mothers’ breasts, dashed them headlong against the rocks. Others, laughing and joking all the while, threw them over their shoulders, shouting, ‘Wriggle, you little perisher.’"