What does "A.M." mean in English for Spanish?

In English for Spanish, "A.M." means:

de la mañana

Listen to "A.M.": (If you have an HTML5 enabled browser, you can listen to the native audio below)

This is a word that is used in the GamesForLanguage English for Spanish Language Game in the following scenes:

• English for Spanish 3, Level 3, Scene 11