Or these guys which look like sheep 
http://media-2.web.britannica.com/eb-media/84/6384-004-47960FCF.jpg
Personally I’d go with a German Shepherd or a Golden retriever. They’re the right size, shape, look, and temperament. Itty bitty dogs tend to be too mean and are more rat like than anything else. A dog should be a worker and I just can’t imagine anything a little dog can do. Snout nosed dogs are too distinctive of a particular breed type, plus they’re ugly. Beagles and other hound dogs are good and their good at tracking but I don’t think they’ll do too well in a fight where they have to defend me. If the dog is too big they lose all their energy and as mentioned above tend to be small ponies.
It’s a bit confusing because the OP is actually asking 2 questions in the first part (and 2 more in the 2nd part). He’s asking what comes to mind when we hear the word “dog” and what we think should go in the dictionary. The answers might very well be different for the 2 questions, and some people are answering only the 1st part. That might not address Chronos’ posts, but it does address others.
I do agree that the dictionary picture should look like a pariah dog, but that isn’t what comes to my mind first-- they are not the most common dogs I’m exposed to. It would be something more like a lab.
I think of a medium-sized dog with wire hair and floppy ears. Something like this.
I write stories for children, and dogs often show up in them. Almost always, they’re yellow Labs. I’ve never had a dog.
They say that the Northern breeds such as Huskies and Malamutes are closest in appearance to the original ‘dog’ when the wolf-dog genetic split occurred. The long snouts, athletic speed and endurance, narrow faces, and cold-resistant fur are direct carryovers from the wolf.
Of course you’ve not had a dog, you’re a tiny french poodle…
If I could pick the dog that is the polar opposite of me, it’s a tiny French poodle. I guess I’d be a Newfie without the intelligence or skills.
This may very well be a special case of Western exceptionalism.
Who is Old Yeller? ol yeller photo - Bing
And I would add that dogs with partial fox DNA should not be included.
Most sight hounds, as long as they’re not abnormally long and tall and thin. Your usual brown coat and a dark snout.
Ah, I found a couple of pictures of Bowser, the Doggiest Dog Ever:
Bowser with Ms. Mousey (he’s the one on the right)
Bowser asleep
(hopefully those links work right)
I nominate “Bowser” as the doggie-namest doggie-name. Or maybe Fido.
The “dog shaped” dog I have is the same shape - no white, and the brown on Bowser is darker and reddish. (And right now is in possession of a stuffed ring that he is tossing around like a puppy and a big foolish dog grin on his face).
And a very catly cat, too. I, like most of the cat owners here I suspect, had one that looked just like her.
Doggiest looking, I’d go with a Lab.
Ugliest? Little fluffy white dogs. They look like wads of used toilet paper, with eyes. The Benji types are unattractive too.
Least dog-like? Chihuahuas.
Whatever I may say about them, I’m sure there is no breed of dog that I wouldn’t love, if I knew one. Dogs are the best thing in the world.
Mine has body shape much like Chronos’ Bowser, but she’s all black (Black Lab/Australian Shepherd mix). She seems very doggy to me, but I’ll agree that the variegated coat is doggier.
Floppy-eared shepherd mix, as that’s been the most common dog besides pit bulls/mixes everywhere I’ve ever lived.
I have a doberman, a kangal and a golden retriever x standard poodle. The last looks like a teddy bear, hardly a dog at all but he has the quintessential ‘doggy’ personality - enthusiastic, goofy, friendly. The other two are guard dogs, more reserved and serious generally and they dislike strangers.
This is Rex he’s got a very doggy name and is pretty doggy looking.
At a hundred pounds he may fall into the small pony category. I had to test he DNA t make sure he was a dog, so that probably disqualifies him.