1. A piece of land cleared of trees and usually enclosed Noun
2. A region where a battle is being (or has been) fought Noun
3. Somewhere (away from a studio or office or library or laboratory) where practical work is done or data is collected Noun
4. A branch of knowledge Noun
5. The space around a radiating body within which its electromagnetic oscillations can exert force on another similar body not in contact with it Noun
6. A particular kind of commercial enterprise Noun
7. A particular environment or walk of life Noun
8. A piece of land prepared for playing a game Noun
9. Extensive tract of level open land Noun
10. (mathematics) a set of elements such that addition and multiplication are commutative and associative and multiplication is distributive over addition and there are two elements 0 and 1 Noun
11. A region in which active military operations are in progress Noun
12. All of the horses in a particular horse race Noun
13. All the competitors in a particular contest or sporting event Noun
14. A geographic region (land or sea) under which something valuable is found Noun
15. (computer science) a set of one or more adjacent characters comprising a unit of information Noun
16. The area that is visible (as through an optical instrument) Noun
17. A place where planes take off and land Noun
18. Catch or pick up (balls) in baseball or cricket Verb
19. Play as a fielder Verb
20. Answer adequately or successfully Verb
21. Select (a team or individual player) for a game Verb