This is the 3664th most frequent Russian word.
театре
"Театре" is the prepositional case of "театр," meaning "in the theater."
In this sentence, 'театре' is used as the prepositional form of the noun 'театр' (theater), indicating location.
Я был вчера в театре.
I was at the theater yesterday.
Here, 'театре' is used to specify the theater in which the described event (a performance) took place.
Мы с удовольствием посетили спектакль в вашем театре.
We enjoyed attending a performance at your theater.
In this example, 'театре' refers to being employed or engaged in activities within a theatrical venue, using the word metaphorically to signify the theatrical profession.