Trocadéro can be understood to be either the plaza that stands across the river from the Eiffel Tower, or as the overall hill that includes more than just the plaza - two theaters, a restaurant, and several museums, including, making your way down the hill, the musée de la marine, musée de l'homme, the "cinéaqua" aquarium, the city's modern art museum. Across the way is the palais Galliera, ie the fashion museum. You also have the Tokyo Palace and Museum of Modern Art near to it so it's really a good place for Museum. 

 You have good restaurants in the Plaza such as "Carette" : one of the best parisian patisserie/ bakery, and the brunch is insane !