Half fruitcake in queer is a term that is derogatory and is used to insult or even demean gay people.
Half fruitcake in queer used as an insult or demeaning of gay is also often used with connotations of effeminancy or perceived madness.
Although the term fruit itself is also used in a similar way, the word fruitcake also adds a layer of negative association due to the word cake.
And sometimes the idea of being nutty or crazy.
And the term is also considered to be a slur and should not be used, especially towards LGBTQ+ people.
A synonym for nutty as a fruitcake would be crazy or even barmy, zany, daffy, wacky, idiotic or mad.
Even loopy, dotty, demented or deranged are also other synonyms for nutty as a fruitcake.
Nutty as a fruitcake is a term that refers to someone that is idiotic or crazy.
An example of how to use nutty as a fruitcake in a sentence would be.
John is as nutty as a fruitcake if he thinks he can get that elephant to fit inside of his car.
The adjective nutty meaning "insane" was also first recorded in the year of 1821.
And the similarity to the fruitcake, which literally does contain nuts as well as fruit, was also first recorded in 1935.
When someone says you are a fruitcake it means the person is saying that you are a crazy or eccentric person or a nut.
If you are a very strange or crazy person then someone would refer to you as being a fruitcake or nutty as a fruitcake.
if you do something or are about to do something crazy or idiotic then you would also be nutty as a fruitcake or just be a nut.