Alien definition of beauty

I was thinking about how aliens that are defined as "beautiful" are defined by our standards. But what if aliens have entirely different standards when it comes to beauty? What could they find beautiful?

That's a very curious choice of words since we have our own problems identifying what beauty is. As in, we could describe a time, place, person, concept, art piece, book, and so on as beautiful. So with this in mind we can agree that we don't use beautiful exclusively for physical appearance. But does that mean those listed things have objective qualities or beauty, or are we just saying we think it's beautiful, like "in the eye of the beholder"? If it is the latter, then we as humans wouldn't be able to agree that anything is beautiful. That makes the phrase "I think this is beautiful" mean "I like this" rather than "beauty can be found in this." Because nothing in inherently beautiful in this mindset, it only becomes that way after an individual thinks that of it, and still only to that person. But more getting back to the relevant question, I think much of it comes from cultural influences. I believe that most humans find passion to be something beautiful, such as we could watch an opera in another language and appreciate its beauty, though we might not understand it. Would that be the same with aliens? Doubtful, too many uncertains. Would an alien even have a concept of beauty, or do they experience other things that we don't? It's a fun thought process, but to keep it short, I don't think we would have any similar standards of beauty with aliens.