giddy

Short definition from Wiktionary

Adjective

1. 1
   Feeling a sense of spinning in the head, causing a perception of unsteadiness and being about to fall down; dizzy.
2. 2
   Causing or likely to cause dizziness or a feeling of unsteadiness.
3. 3
   Moving around something or spinning rapidly.
4. 4
   Unable to concentrate or think seriously; easily excited; impulsive; also, lightheartedly silly; frivolous.
5. 5
   Unable to concentrate or think seriously; easily excited; impulsive; also, lightheartedly silly; frivolous: Used as an intensifier.
6. 6
   Joyfully elated; overcome with excitement or happiness.
7. 7
   Feeling great anger; furious, raging.
8. 8
   Of an animal, chiefly a sheep: affected by gid (“a disease caused by parasitic infestation of the brain by tapeworm larvae”), which may result in the animal turning around aimlessly.
9. 9
   Of a thing, especially a ship: unsteady, as if dizzy.

Noun

1. 1
   Someone or something that is frivolous or impulsive.
2. 2
   Synonym of gid (“a disease caused by parasitic infestation of the brain by tapeworm larvae”).

Verb

1. 1
   To make (someone or something) dizzy or unsteady; to dizzy.
2. 2
   To become dizzy or unsteady.
3. 3
   To move around something or spin rapidly; to reel; to whirl.

Proper noun

1. 1
   A surname.