Giddy (adjective)

1. Feeling dizzy or unsteady, as if about to fall.
2. Feeling lightheaded or faint, as from a rush of blood to the head.
3. Feeling excessively exhilarated or elated.

Origin:

From middle english word "gidie" meaning dizzy, lightheaded.

Examples:

1. He felt giddy after spinning around.
2. She felt giddy when she saw him after so many years.
3. The giddy heights of the roller coaster made him feel sick.
4. The giddy feeling of falling in love made her heart race.
5. The giddy atmosphere of the party made her feel dizzy.