halo

Short definition from Wiktionary

Noun

1. 1
   A circular band of coloured light, visible around the sun or moon etc., caused by reflection and refraction of light by ice crystals in the atmosphere.
2. 2
   A cloud of gas and other matter surrounding and captured by the gravitational field of a large diffuse astronomical object, such as a galaxy or cluster of galaxies.
3. 3
   Anything resembling this band, such as an effect caused by imperfect developing of photographs.
4. 4
   nimbus, a luminous disc, often of gold, around or over the heads of saints, etc., in religious paintings.
5. 5
   The metaphorical aura of glory, veneration or sentiment which surrounds an idealized entity.
6. 6
   The bias caused by the halo effect.
7. 7
   a circular annulus ring, frequently luminous, often golden, floating above the head
8. 8
   A circular brace used to keep the head and neck in position.
9. 9
   A roll bar placed in front of the driver, used to protect the cockpit of an open cockpit racecar.
10. 10
    Ellipsis of halo headlight.
11. 11
    Acronym of high altitude, low opening (“a type of skydiving where one leaves the launch platform from a high altitude and opens the parachute at a very low altitude”).
12. 12
    Acronym of hazardous area life-support organization.
13. 13
    Acronym of high altitude, low orbiting.
14. 14
    A member of the Angels Major League Baseball team.

Verb

1. 1
   To encircle with a halo.