A Dirty Alastair is a person that enjoys a colonoscopy far too much for the comfort any doctors or nurses performing the procedure.

Oftentimes they will book unessassary colonoscopies for no other reason than boredom, or to avoid their other personal or professional obligations.
John won't be at the clientcmeeting this afternoon, he's pulled a Dirty Alastair again...Those poor nurses.
by SCKnocking September 12, 2021
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--Proper noun

An affiliation dedicated to the celebration of Alastair Sim as Ebenezer Scrooge in The Christmas Carol (1951). This group often rumbles with the Reginald Owen's Boys, who have opposing views on the matter. The rumbles happen annually around Christmas time, and often take place in local parks.
Werewolf: Who's your favorite Scrooge?
Dunce: Patrick Steward.
Werewolf: And this is why you'll never be part of the Alastair Sim Boys.
by theedingo1 November 18, 2010
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One must always look up to him, as he is not man, but a being so powerful and majestic that all of humankind must watch in awe and disbelief at his form. TAM is one to be revered, one to be feared, one to be worshipped, one to be sacrificed for, one to put above the belief or ideas of all else. TAM is not God, but he is above God, and he shall be treated as if nothing else in the world possesses any minute value, as all universal importance stems from TAM.
Give your life for Timothy Alastair McLain or you will be as worthless as a woman.
by Elizabeth Shuk the Third October 12, 2021
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When a victory is reduced in skill because the team you beat has Alastair on it
“Wow , that was a good win against Vietcong
“Nah , it’s was pretty average , you’re forgetting about Alastair Tax
by BigManBurmo January 28, 2021
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Alastaire is always worried about his friends and not himself
by Oh Yuuup October 18, 2018
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Alastair McCrae is a little man
Dan: “Do you know Alastair McCrae?”
Sam: “no”
Dan: “exactly
by HealyMeister January 8, 2022
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