Raving means talking wildly, the way somebody does in a fever. Words pouring out with no order in them.
The literal sense belongs to delirium and to breakdown: raving in his sleep, taken away raving. From there it became an intensifier, and a raving lunatic is simply a very mad one. It also went the other way entirely, since a rave review is a wildly enthusiastic one and to rave about a restaurant is to praise it without stopping. The noun rave took a third path in the 1980s and became an all-night dance party.
1adjectiveravingTalking wildly and incoherently, as in delirium.
“He was found raving in the street.”
2adjectivestrengthenUsed to strengthen an insult.
“She called him a raving idiot.”
Practised in A Man Called Ove, A Song of Ice and Fire
First appears in chapter 20 of A Man Called Ove.
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