Cracker in British slang means something is of very high quality or excellent.
Cracker in British slang can also be a derogatory term, although the derogatory term of cracker is less common in modern British slang.
The term "cracker" originated in the 16th century, and initially meant a braggart, but it's positive meaning in British slang today is what refers to something that is exceptional, such as a "cracker of a goal" in football or a "cracker of a show".
Another similar slang word is cheese and crackers which in slang means "disbelief" or a "mild exclamation of surprise".
Cheese and crackers in slang can also mean "annoyance" or even used by someone as a playful substitute for stronger swear words.
The slang "cheese and crackers" can also be used to express "amazement" or even "wonder".
The meaning of cheese and crackers in slang is not literal and is similar to other minced oaths like "darn it" or "gosh".
When expressing amazement, cheese and crackers can be a way of showing genuine excitement or awe over something positive.
When used to express disbelief surprise, cheese and crackers can be used when something surprising or something unexpected happens to them or someone like saying "Oh, no!", or "Oh, Wow!".
And when used as a minced oath, the slang cheese and crackers serves as a soft alternative to swear words like, "Jesus Christ".
When someone calls you or says to you "cheese and crackers" it's a mild and playful substitute for stronger swear words and is like saying "shoot" instead of some harsher words.
Cheese and crackers is also a nickname for a girl whose vagina smells of cheese and crackers, generally after fingering cheese and crackers, the smell will linger for several hours.