A defence mechanism in any slightly confrontational situation that can either be hilarious if used in an innovative way or make you look like a complete idiot (hence the phrase being common place with chavs and other nonentities).
# please a your mum joke can only be humourous if you use a mocking voice to show that you are merely taking the mick out of someone who would use sucha phrase and think it were hilarious (i.e. a nonentity)
reasonably good use of the phrase-
fred: 'my word it is hot today'
george: 'so was your mum last night after i roasted her over the table (alright, gigidy gigidy!)' #said in a mockingly moronic tone

bad use of the phrase-
Ben:'did i here you got an E in english language Lewis?'
Lewis: 'your mum (wayyyyyyyyy)' #said in a hereditary moronic tone
by dan baylis March 22, 2007
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To be used in several, subtely different ways.
Situation #1
A: "Your gay*"
B: "Your mums gay"
A: "Your face is gay"
B: "Your ex is gay"
A: "True"
B: "oh noes!"

*In this situation, the term gay is used in a non-derogatory to homosexuals kind of way. In this context, it means stupid and annoying.

Situation #2
A: "You know xyz..."
B: "You know what, your mum"
A: "YOUR mum!"
B: "Yeah well, your mum sucks cock"
A: "Well, your mum sucks my dads cock"
B: "You suck cock"
A: "Your face sucks cock"
B: "Your ex sucks cock"
A: "True"
B: "oh noes!"
by Izzy Pop May 5, 2006
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Contrary to the above suggestions the term "your mum" is not actually officially an insult. In fact, in many situations it can be seen as a very honourable compliment. For example, if someone calls your mum a "hottie", you can revel in the knowledge that you were first out of all your friends to be in her (provided none of your friends have entered her previous to your birth, might be best to check first). Additionally, your mum might be called "loose" and a "fucking slag" which are street terms for being a good listener.

However, there are certainly usages which can be deemed offensive, as we can see below in the examples. In fact, the British government in the "Your Mum" parliamentary act of 1923 split the term into 5 classes. Use of a level 5 can lead to unlimited fines and/or a prison sentence of 20 years. Community service for a level 4 usage is compulsory, servicing 40+ year old mums to 'keep them fresh'.

(History)

The term was first coined by early Christians after the Bible story in Bernard 3:19 in which Jesus is still a teen and beginning his forages into carpentry and the bush. In the account he is bullied by a gang of locals nicknamed 'The Disciplz', who continually shout abuse and throw pasties at his knees . Eventually, Jesus tires of the pastry-related insults and hits back with his best friend Foreskin, cornering the Disciplz and threatening them with a badger. His tormentors are reluctant to repent until Jesus speaks the most momentous words that possibly the whole world has ever heard...

"Your mothers are all very much like the Romans. They are strong, valiant and innovatice, and they all wear skirts that show their willies."

In the story the Disciplz immediately fall to their knees and pledge allegiance to Jesus, scratching their elbows with shortcake as was the age-old tradition and not leaving his side for 20 more years, even to go to the loo.

Inevitably the usage grew from that point but the term has been somewhat tainted by popular culture and Richard and Judy. We can only pray that those who use it correctly shall be rewarded with the "Second Coming (Of Your Mum)"...
Level 1 - Much favoured usage in the Western world

'Your mum has a massive cock and I am going to stick it in my mouth and inflate her already huge

Level 2 - A passable compliment

'I would love to take your mum out sometime and penetrate her, if that is ok with you'

Level 3 - Risky, preferably used behind closed doors

'Your mum likes chocolates because they are the same colour as my poo'

Level 4 - Offensive and nasty use - would make me cry

'Your mum is an idiot. She has the IQ of an elf.'

Level 5 - You must be a mental

'Your mum is a M*ll*rd Duck'
by Ludovig January 25, 2007
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your mum
oi Charlie cuz your mum blud
by gullyguyleo November 20, 2016
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an insult targeted towards another persons mother.
idiot: insert insult here
other idiot: YOUR MUM!!
by Joey June 13, 2003
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your mum insults - nottingham style!! keeping it real - your mum keeps it real. It smells of fish in here - your mum smells of fish. Tell your mum I wont be coming round tonight because I am doing your gran. Later

I saw your mum walking down the road kicking a cardboard box, I said what you doing? She said - I is moving house, innit!?

I saw you mum walking down the road with a wok on her head and a wooden spoon in her hand, I said what you doing? - She said I is playing Robocop, innit!?
by George Chelle February 22, 2008
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1. The woman who gave birth to you
2. Attempted insult,or come back, normally from a townie , normally pathetic, normally not very insulting, normally making little or no sense.
1.... explains itself doesn't it?
2.
A)Townie: Are you Jack Osbourne?
Me: No, my name's Chaz
Townie: Your Mum's Jack Osbourne!
B) <townie is standing in middle of path so people cant get past, cos he's such a badass>
Me: can you get out the way please?
Townie: <leaving quickly> your mum for men!
by Chaz April 17, 2004
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