Main Entry: mi·graine

Pronunciation: \ˈmī-ˌgrān, British often ˈmē-\

Function: noun

1 : a condition that is marked by recurrent usually unilateral severe headache often accompanied by nausea and vomiting and followed by sleep, that tends to occur in more than one member of a family, and that is of uncertain origin though attacks appear to be precipitated by dilatation of intracranial blood vessels
2 : an episode or attack of migraine <suffers from migraines>—called also sick headache

—mi·grain·ous \-ˌgrā-nəs\ adjective