Fawn has two completely different meanings:

1. A baby deer, especially one still young enough to have white spots on its reddish-brown coat. In spring, you might spot a fawn resting quietly in tall grass while its mother grazes nearby. Fawns can walk within hours of being born, but they spend their first weeks lying still and camouflaged, waiting for their mothers to return and nurse them. The word fawn can also describe the soft tan color of a young deer's coat.
2. To act extremely nice to someone, often in an exaggerated or insincere way, usually to gain something from them. When someone fawns over a teacher hoping for a better grade, they shower them with compliments and eager agreement. You might see this behavior when a student suddenly becomes overly helpful and flattering right before report cards come out. The word carries a negative tone because it suggests the person isn't being genuine. They're putting on a show of admiration or obedience to manipulate the situation, like a dog that rolls over and wags frantically when it wants a treat.