Slangs are the expressions which are used in their most informal usages.Slang is language at its most informal, using expressions that many would consider to be grammatically imperfect and sometimes rude. Slang often used within small social groups where it can help draw and keep the group together. It changes very quickly in English.
Cockney Rhyming Slangs are the specialised forms of slangs used in the East of London. This kind of Slang is a kind of antilanguage where words are replaced by phrases that rhyme (sound the same): North and south = mouth Adam and Eve = believe Sometimes, the last word is dropped.
Slangs beginning with M :
Main drag : The main drag is the most important street in a town or city.
Make a bundle : If you make a bundle, you make a lot of money.
Make a stink : If someone makes a stink, they make a fuss and cause trouble.
Make mincemeat : If you make mincemeat of somebody, you defeat or destroy them completely.
Mampy : (UK) Someone who's mampy is ugly.
Man rat : (UK) Man rats are liars.
Manny : (UK) A manny is a male nanny.
Manor : (UK) A person's manor is their neighbourhood or their area of influence.
Mardy : (UK) Someone who complains a lot or gets upset easily is mardy.
McChildhood : A McChildhood is when parents give their children things that will satisfy them in the short-term but leave them ill-equipped for dealing with more serious issues later in life.
McJob : A McJob is a boring, low-paid job in the retail or service sectors with few prospects. (The prefix 'Mc' comes from the fast food chain McDonald's)
Meathead : A meathead is a stupid person.
Meathead : (USA) Someone who is stupid or goofy is a meathead.
Meg : (UK) Someone who's meg is very embarrassing (Most Embarrassing Guy/Girl).
Mega : If something's mega, it's great. It can also mean a large number or quantity.
Meh : This is used to show that you don't care about something.
Merf : USA) This can be used, normally at the start of an utterance, to express sympathy, shame or indifference.
Michael Jackson : (UK) A Michael Jackson is an amount or number under ten.
Mickey Mouse : If something is Mickey Mouse, it is of poor quality or not to be taken seriously.
Minder : A minder is a bodyguard.
Mindfuck : A mindfuck is something that is so surprising, shocking or complex that it is difficult to comprehend.
Minger : (UK) A minger is an ugly person.
Minging : (UK) If something is minging, it's awful.
Mint : (UK) If something's mint, it's really good.
Mither : (UK) A person who mithers complains a lot.
MoFo : (USA) MoFo is an abbreviated form of 'motherfucker'.
Moggie : (UK) A moggie is a cat.
Mole : A mole is an ugly person.
Montezuma's revenge : Montezuma's revenge is a stomach upset or food poisoning caught on holiday.
Moobies : If an overweight man has moobies, he looks as if he has breasts.
Moody : (UK) If something's moody, it is illegal or fake.
Moolah : (UK) Moolah (or moolar) is money.
Moose : If a person is a moose, they are socially inept.
Moss-back : (USA) An elderly relative is a moss-back.
Motherfucker : (USA) A motherfucker is a despicable person.
Mozzarella : (UK) Mozzarella is money.
Muffin top :A muffin top is a roll of fat exposed when wearing low-cut jeans.
Mullered : (UK) Someone who is mullered is very drunk.
Mullet : A mullet is a hairstyle where the hair is short on the top and sides, but long at the back, and is regarded as tasteless and amusing.
Munter : (UK) A munter is an ugly person.
Muppet : (UK) A muppet is an idiot.
Muscle Mary : A muscle Mary is a gay bodybuilder.
Mushroom : (USA) An innocent person shot in a street fight is a mushroom.
My bad : (USA) If someone says 'my bad' they mean that they have done something wrong and realise it.