The term "half witted" is a derogatory term used to describe someone who is perceived as being foolish or unintelligent. However, it is important to note that this term is insensitive and offensive. There are several synonyms that could be used to describe someone who is perceived as being less intelligent. Some of these words include "simple-minded", "unintelligent", "idiotic", "moronic", "foolish", "stupid", "brain-dead", "dense", and "dim-witted". It is always important to choose your words carefully and avoid using language that may be hurtful or offensive to others.