A headache is a pain or ache in your head, especially one that lasts longer than a few minutes. You might get a headache after a day of staring at a computer screen.

There are many reasons for getting a headache, from staying up too late to a stressful day to skipping your morning cup of coffee. A more serious type of headache, like a migraine, might keep you home from work for a day, but most headaches are just a nuisance. You can also describe a problem or struggle as a figurative headache: "Learning Danish is turning out to be a real headache." In Old English, the word was heafodece.

Definitions of headache
  1. noun
    pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs
    synonyms: cephalalgia, head ache
    see moresee less
    show 5 types...
    hide 5 types...
    cluster headache, histamine headache
    a painful recurring headache associated with the release of histamine from cells
    hemicrania, megrim, migraine, sick headache
    a severe recurring vascular headache; occurs more frequently in women than men
    sick headache
    a headache accompanied by nausea
    sinus headache
    a headache resulting from congestion or infection in the paranasal sinuses
    tension headache
    a headache located at the back of the head; usually caused by body tension resulting from overwork or psychological stress
    type of:
    ache, aching
    a dull persistent (usually moderately intense) pain
  2. noun
    something or someone that causes anxiety; a source of unhappiness
    synonyms: concern, vexation, worry
    see moresee less
    show 7 types...
    hide 7 types...
    a source of concern
    burden, encumbrance, incumbrance, load, onus
    an onerous or difficult concern
    a rightful concern or responsibility
    dead weight
    an oppressive encumbrance
    a burden (figuratively in the form of a bundle)
    an uncalled-for burden
    something unpleasant or offensive that must be tolerated or endured
    type of:
    negative stimulus
    a stimulus with undesirable consequences
Word Family

Test prep from the experts

Boost your test score with programs developed by’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.


  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week


  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week


  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week