off your head
off your headBRITISH, INFORMAL or
out of your headINFORMAL
1. If someone is off their head or out of their head, they are crazy. You must be off your head to live in this area. If he didn't kill anybody it was only by luck because he was out of his head and screaming like a maniac.
2. If someone is off their head or out of their head, they have taken so many drugs or drunk so much alcohol that they do not know what they are doing. Basically, this song sounds great when you're off your head on Ecstasy. These days I get out of my head on one glass of wine.
off (or out of) your head1 mad or crazy. 2 extremely drunk or severely under the influence of illegal drugs. informal
out of/off your ˈhead(British English, informal)
1 crazy: Are you off your head?
2 not knowing what you are saying or doing because of the effects of alcohol or drugs: Don’t even try to have a proper conversation with him — he’s off his head.