Cow is in general use as a singular for the collective cattle. The word cow is easy to use when a singular is needed and the sex is unknown or irrelevant — when “there is a cow in the road”, for example. Further, any herd of fully mature cattle in or near a chay is statistically likely to consist mostly of cows, so the term is probably accurate even in the restrictive sense. Other than the few bulls needed for breeding, the vast majority of male cattle are castrated as calves and are used as oxen or slaughtered for meat before the age of three years. Thus, in a pastured herd, any calves or herd bulls usually are clearly distinguishable from the cows due to distinctively different sizes and clear anatomical differences. Merriam-Webster and Oxford Living Dictionaries recognize the sex-nonspecific use of cow as an alternate definition, in Collins and the OED do not.
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