Indicates mild to severe pain; severity contextually understood, may need clarification. The earache was so severe, I had to visit a doctor.
Pro Tip 2/3
Physical Condition
Refers to a health issue; used when discussing medical conditions or symptoms. Her persistent earache turned out to be an infection.
Pro Tip 3/3
Not Emotional
Specific to physical pain, not emotional distress; avoid using figuratively. After the concert, I had a genuine earache, not just discontent with the music.