What does the term "opposite" mean in acting?

No it means he was a star of equal standing in the cast with the others named. You could say, for example, that Jake Gyllanhaal played opposite Anne Hathaway in Love and Other Drugs.

thank you. :)

It’s usually used for co-stars when there are two main ones, most commonly a male and female lead: Clark Gable starred opposite Vivien Leigh in Gone with the Wind. If I saw it used for a string of names I would think it rather odd because unless it is a true ensemble cast, there is rarely a group of stars at peer level in the film.

@Jeruba is correct. The Parrish bio really should have said that he appeared with or alongside Zac Efron, etc., or that he “co-starred” with them. “Opposite” is more properly used as Jeruba explained.

Yes, but the connotation has grown so the above usage is pretty common. It means “starred with” or more loosely “acted with” . I’m not sure that by definition it means that they have equal standing in the cast though generally they would. I think the distinction could probably made that this is reserved for principal cast. If you had a small speaking role in a movie with Julia Roberts you would never say you played “opposite” Julia Roberts. But if you are a notable actor like the actor above and didn’t really star in the movie but you were significant in the ensemble you could probably say you were opposite “Zac Efron. Matthew Perry, Leslie Mann, etc.” But if there was only one name you were paired with and you were not romantic leads or the two main actors (i.e. Robert Redford opposite Paul Newman in Butch Cassidy and the Sundance Kid) it might be odd to use the word opposite.

I construe it to mean that when actors play opposite another actor that it meant that they had roles of similar weight (lines, screen time) and were equally important to the production, because their characters’ interaction contributed to the overall story line in a similar manner.

If I am playing opposite you, then our dialogue is going to shape the story in some way. Co-stars would refer to billing of the actors, which has nothing to do with the character interaction.

True, @BarnacleBill that’s a good point- I think to @Jeruba ‘s point- this is were the term opposite came from. It would be odd for you to play opposite someone and not interact with them in the film. Probably in it’s purest form- the term had to do with the central romantic relationship between two billable stars of equal stature. But it’s obviously being used pretty loosely in some contexts these days.