1. field, field of operations, theater, theater of operations, theatre, theatre of operations, region
usage: a region in which active military operations are in progress; "the army was in the field awaiting action"; "he served in the Vietnam theater for three years"
Noun
1. field, field of operations, theater, theater of operations, theatre, theatre of operations, region
usage: a particular kind of commercial enterprise; "they are outstanding in their field"