How do you spell Ache

Available Definitions:
1)  n. - A name given to several species of plants; as, smallage, wild celery, parsley.
2)  v. i. - Continued pain, as distinguished from sudden twinges, or spasmodic pain. "Such an ache in my bones."
3)  v. i. - To suffer pain; to have, or be in, pain, or in continued pain; to be distressed.