vig·i·lan·te 
(vĭj′ə-lăntē)
(vĭj′ə-lăntē)n.
A person who is not a member of law enforcement but who pursues and punishes persons suspected of lawbreaking.
[Spanish, watchman, vigilante, from Latin vigilāns, vigilant-, present participle of vigilāre, to be watchful, from vigil, watchful; see weg- in the Appendix of Indo-European roots.]
vig′i·lantism (-lăntĭz-əm), vig′i·lante·ism (-tē-ĭz′əm) n.
- Aton
- Aton
- atonable
- atonal
- atonalist
- atonality
- atonally
- at once
- atone
- at one
- atoneable
- at one fell swoop
- atonement
- atoner
- at (one's) elbow
- at one's elbow
- at (one's) expense
- at one's expense
- at (one's) fingertips
- at one's fingertips
- at (one's) leisure
- at one's leisure
- at (one's) wits' end
- at one's wits' end
- at one time