While a dog's vocabulary isn't quite as extensive as ours, a new study reveals that the average dog can respond to 89 words or phrases on a constant basis. Nearly half are orders, such as "sit" or "stay," but certain generic terms, such as "wait," and nouns, such as "treat," are also recognized.

The most intelligent pups were discovered to respond to almost 200 specific words, roughly equivalent to a two-year-old human child's vocabulary.

Obviously, a dog does not pronounce these words in the same way that a child does, but dogs do appear to respond to particular words in a predictable and consistent manner, implying that they have some level of language comprehension.

The results are based on a well-known vocabulary checklist that parents use to evaluate a human infant's vocabulary. In this case, however, it was supplied to 165 dog owners, who included dogs of various breed types, ages, and occupations.

While the extent of a dog's vocabulary seems to be influenced by breed type and work position (for example, a police dog), its age and the qualities of its owner did not appear to have an impact.

"Based on owner reports, dogs seem to vary greatly not only in the number but also in the kinds of words to which they purportedly respond," the authors of the new study wrote.

In the past, studies have shown that with intensive training, dogs may learn to reply to an astonishing amount of human words. Researchers reported in 2004 on a border collie named Rico that had learned to recover over 200 items simply by hearing their names, including "stuffed toys and "balls."

Another border collie had a toy vocabulary of over 1,000 words after three years of training in 2011. Some canines are so clever that they can learn new language after only hearing them a few times.

But what about your typical family dog?

The authors of the current study used an online survey to ask dog owners how their pets reacted to 172 words and phrases.

With this type of study, there's always the risk that the owners will exaggerate their pet's comprehension. However, earlier studies on this specific language test among infants indicated that parents understand their children better than a trained observer, so the same could be said for their dogs.

There's always the possibility that the dogs in the study were interpreting specific words based on human gestures and other contextual information. Furthermore, because many of these dogs had had basic obedience training, it's possible that an untrained dog's vocabulary might be lower than 89 words.

The study was published in Applied Animal Behaviour Science.