Learn Spanish (Spain): Una docena de huevos, por favor.

Docena is a noun meaning "a dozen" or "a group of twelve." Just like in English, when you use a noun of quantity, you link it to the item with de (of): "a dozen of eggs." If you use the number doce (twelve), you put it directly next to the noun without de: doce huevos.

Is una docena feminine even though huevos is masculine?

Yes! Docena is a feminine noun, which is why it uses una. Its gender is fixed and doesn't change based on what is in the dozen. So you will always say una docena de... whether you are buying huevos (masculine) or manzanas (feminine).

How do I pronounce huevos? Is the h pronounced?

The h is completely silent. You pronounce it starting right with the u, sounding like "WEH-bos." Also, remember that the v in Spanish is pronounced like a soft English "b" when it is between vowels.

Can I ask for half a dozen using a similar phrase?

Yes! To ask for half a dozen, you say media docena. For example: Media docena de huevos, por favor (Half a dozen eggs, please). Notice that it is media (feminine) to match the feminine noun docena.