Meaning

• A reproach, gibe or taunt.

• A foolish or annoying person.

• A euphemism for "twat", a contemptible or stupid person.

• A person who twitters, i.e. chatters inanely (see usage notes).

Meaning

• To reproach, blame; to ridicule or tease.

• To ignore or killfile (a user on a bulletin board system).