"Son lágrimas de alegría."
Translation:They are tears of joy.
I'm in the allergy season. That was my first guess as well and I was looking for the word. Then I realized...
so sometimes I do a google image search on a phase from duolingo. when i search on "lagrimas de alegria" I get images of decorated tissue for weddings. It looks like in Portuguese "lagrimas de alegria" may refer to something that gets handed out at a wedding where lots of tears of joy are expected. Comments and corrections welcomed!
Christiaan14 is correct, but I want to clarify that "tears of joy" is a common English expression. "Happiness" is not an uncommon word.
alegría is almost being used as an adjective, not as an abstract noun, so no article used here (Sorry, this answers your question below!)
Oh, I think I understand. Just like "blue" in "tears of blue"? That's helpful, thanks!
I thought you needed a definite article in front of nouns that are referred to abstractly. Why doesn't "alegría" need one here, even though you are referring to happiness in general?