British slang, originating from Pilsley, Derbyshire: A weak expletive which shares both its
definition and conventions of use with the word bastard. Originally, "mustard" was used to refer to a child born out of wedlock, but through a process of semantic broadening, it is now mostly used as a general pejorative term. It can be used both as a noun (see example one) and an adjectival intensifier (see example
two). The word bastard is used in precisely the same way. As an antidote to your ignorance, other examples of intensifiers are: fucking,
bloody, chuffing, sodding, etc.