head ache is a noun meaning "pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs". It carries one recorded sense.
pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs
Definitions, synonyms and semantic relations for head ache come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.