The phrase "terrible migraines" refers to severe and extremely painful headaches that can cause a lot of discomfort and affect someone's ability to do their daily activities. Full definition
TUESDAY, Dec. 21 (HealthDay News)-- Judy Brown says she has suffered from terrible migraine headaches since she was in her teens. (health.com)
Then I could spend my life fighting the food industry re MSG instead — I get terrible migraines from it & it's hidden under some 50 different names, new ones cropping up all the time. (realclimate.org)