[AEMILIUS PAULUS]

Dogs associate the sounds(or body movements) with reward NOT the meaning of the word. Example, when I tell my dog "Cookie" pronounced in a certain fashion she goes to the back door and waits. If I say "Boodie" in the same tone then off to the back door and she waits. There are many many variables in a situation that must be controlled before one can pin point the understanding of the meaning of words and terms.

[Desdemona]

Dogs associate the sounds(or body movements) with reward NOT the meaning of the word.

Baloney. When my lab was younger (she's now 11 1/2), you could say "walk" to another person in the room and she'd go nuts. She could be sound asleep and that word would evoke a response. Frisbee was the other word. Say it and she'd go dig it out of the crate with her toys.

[R. Scott]

If you raise a child using “"Cookie" or “"Boodie" - in the same tone - as meaning “back door” it will learn that they both mean “back door”.
That’s one of the reasons I hate to hear parents using baby talk with their infants. I’ve seen a case where the poor kid was starting preschool and thought “foo-foo” meant vacuum cleaner, “din-din” was the only word it knew for breakfast, lunch or dinner and “go-go” was a car.