the·ater (US) or chiefly Brit the·atre 
/ˈθijətɚ/ noun
plural the·aters /ˈθijətɚ/ noun 1 [count] a : a building where plays, shows, etc., are performed on a stage
▪ the oldest theater in the city ▪ a theater performance ▪ the theater district in New York City — see also dinner theater
b US : a building or room in which movies are shown
▪ The film is now showing in theaters. ▪ a movie theater ▪ a home theater 2 [noncount] a : plays in general or as a form of entertainment
▪ We enjoyed a weekend of music, dance, and theater. ▪ He was very fond of the theater and had purchased tickets for several performances. ▪ Her interests include theater and poetry. ▪ the theater of 16th-century England ▪ a theater critic
b : the art or activity of performing in or producing plays on a stage
▪ She majored in theater in college. ▪ a course in American theater ▪ His monologues made for good theater. ▪ The play makes lively theater. ▪ a theater troupe/company — see also community theater 3 [count] a : a place where important events or actions occur — usually singular ▪ the theater of health-care reform
b : a large area where there is a war
▪ He fought in the Pacific theater (of operations) in World War II. 4 [count] Brit : operating room
▪ the oldest theater in the city ▪ a theater performance ▪ the theater district in New York City — see also dinner theater
b US : a building or room in which movies are shown
▪ The film is now showing in theaters. ▪ a movie theater ▪ a home theater
▪ We enjoyed a weekend of music, dance, and theater. ▪ He was very fond of the theater and had purchased tickets for several performances. ▪ Her interests include theater and poetry. ▪ the theater of 16th-century England ▪ a theater critic
b : the art or activity of performing in or producing plays on a stage
▪ She majored in theater in college. ▪ a course in American theater ▪ His monologues made for good theater. ▪ The play makes lively theater. ▪ a theater troupe/company — see also community theater
b : a large area where there is a war
▪ He fought in the Pacific theater (of operations) in World War II.
