a crack 

Being a crack is simply being brainless and idiotic.

“Yousif likes lemon-head, what a crack”

a crack by Marzook742 March 25, 2019

a crack 

before it was associated with any type of drug. Every one knew that "a crack," was corporal punishment doled out usually from a teacher or school principle at the end of a paddle or other type of manufactured board and applied to the misbehaving students posterior ( butt crack) this was well known slang (1960's-early 80's)

he's on the way to the principles office, and I bet he gets "a crack."

a crack by Swago-soul February 12, 2020

have a crack 

Aussie slang meaning to 'give it a go'

Aww, that jigsaw puzzle doesn't look too hard... Let me have a crack at it!

have a crack by ApexB October 8, 2005

Step on a crack, break your mother's back 

This is an old children's game, anyone who trod on the cracks between the paving stones was out, until only one player was left, he or she was then declared the winner.

Step on a crack, break your mother's back– Most of us know the old rhyme “Step on a crack, break your mother’s back.” Whether the rhyme is the cause of, or a result of, this superstition is uncertain, though belief in it persists in many people today, even if subconsciously. Come to think of it, avoiding sidewalk cracks is probably a good policy for anyone who wants to avoid tripping.

Step on a crack, break your mother's back by WormBrian October 25, 2009

Jack In a Crack 

Jack In The Box- A fast food restaraunt.

Man. I'm hunry! Let's eat at Jack In a Crack.

Jack In a Crack by gundamNIT January 15, 2003

I'll give it a crack

Australian Slang. Means the person will try their best.

John: "Jim do you think you could assist me with putting together this wardrobe?"
Jim: "I'll give it a crack!"

I'll give it a crack by Unquenchable February 23, 2017

Have a Crack 

Australian slang term for having a go at it
Derives from the phrase “have a go”

“have a crack at it mate”
Meaning to have a go at it

By Blake

Have a Crack by Mr_Fitz February 20, 2018