Some dogs struggle to master 'sit' and 'lie down', but according to a new study, canines understand a whopping 89 words and phrases on average.
Researchers in Canada surveyed 165 local owners of a variety of dog breeds about the different words and phrases that their pets understand.
On average, owners reported that their dog could respond to 89 terms, with one particularly clever canine reportedly able to comprehend 215 in total.
Commands make up the majority of words to which dogs reportedly respond to, the authors found, including classics such as 'sit', 'roll over' and 'lie down'.
Almost all dogs were reported to respond to their own name, and most responded to commands like 'sit', 'come', 'down', 'stay', 'wait', 'no', 'OK' and 'leave it'.
However, formal training will likely be required for dogs to learn to respond to as many words as the brightest dogs, the researchers admit.
Looking at dogs by breed, herding dogs including Australian Shepherd, Border Collie and German Shepherd, and toy-companion dogs including Bichon Frise, Cavalier King Charles Spaniel and the Chihuahua, were found to respond to more words and phrases than other breed types.
'Sit!' It's clear that the average domesticated dog understands at least a handful of words. The new research has quantified the size of the average dog's vocabulary through a survey of owners (stock image)
The new study was conducted by Catherine Reeve and Sophie Jacques, researchers at the Department of Psychology & Neuroscience, Dalhousie University, Canada.
'Due to their evolutionary history and close association with humans, domestic dogs have learned to respond to human verbal and nonverbal cues at a level unmatched by other species,' they said.
'Their ability to respond to communicative cues is critical for the numerous professional and family roles they play in our lives.
'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 current study is consistent with existing research suggesting that dogs may be particularly adept at responding to commands rather than object words.'
As early as 1928, scientists have sought to assess the ability of dogs to comprehend what humans say to them.
In that year, psychologists C.J. Warden and L.H. Warner documented the ability of Fellow, a young male German Shepherd, to respond to spoken commands by his owner.
Fellow was observed to respond appropriately to roughly 68 words or phrases, including phrases such as, 'go outside and wait for
