The word is several iterations away from the ancient Latin word for "head" (caput), which was followed by the medieval word for "money" (capitale), which morphed into the Anglo-Norman term for property and livestock, "catel" and eventually became the English word, cattle. The source terms all refer to the value of the animals in trade and abstractly to our way of counting them (i.e. head of cattle). Vocabulary regarding cattle is often based in monetary value.