Here's a breakdown:
* Parlez: The imperative form of the verb "parler" (to speak)
* des: A contraction of "de les" (of them)
* jeune: Young (feminine adjective)
* femme: Woman (feminine noun)
The phrase translates literally to "Speak of the young women", but in English it's more natural to say "Talk about the young women".
It's important to note that the phrase refers to multiple women, as "femmes" is plural.