ha'penny 

2. A chiefly British word for the vulva. Used as a euphemism in music hall songs. E.g. Keep Your Hand On Your HA'PENNY purported to provide tongue-in-cheek advice from "Mom" to daughter Molly on how to keep out of trouble on dates. The refrain of that song ran

Keep your hand on your ha'penny
Cover it well with your palm
Keep your hand on your ha'penny
And Molly will come to no harm.

KEEP YOUR HAND ON YOUR HA'PENNY

When Molly began to go courting
Her mother was anxious to tell
How certain young fellas would want her
to stray down the pathway to 'ell
So Molly's old ma used to say:

cho: Keep your hand on your ha'penny
Cover it well with your palm
Keep your hand on your ha'penny
And Molly will come to no harm

They'll hug you and kiss you so sweetly
They'll make you feel ever so nice,
But handle the fellas discretely
And follow this simple advice:

When Molly and I went out courting
I told her she'd nothing to fear
But down in the meadow last Sunday
I whispered these words in her ear

Take your hand off your ha'penny
Look into my bonny blue eyes
Take your hand off your ha'penny
And I'll give you --- a lovely surprise!

ha'penny by Sean Kerry August 19, 2012

ha'penny 

Ha'penny is a scottish word for vagina.

Shows your ha'penny, cover your ha'penny,stop feeling your ha'penny, stop fingering your ha'penny and hide your ha'penny.

ha'penny by Lucas Bolton April 4, 2006

ha'penny 

Half a penny. One half of 1 Pence in UK currency.

Definitions on urbandictionary are worth ha'penny, one quarter of a fifth of fuck all.

ha'penny by Your fat mothers pswudonym August 16, 2022

Twopence ha'penny millionaire 

A person who pretends to have millions of pounds in the bank, but actually struggles to find a penny to scratch their ass with (A twopence halfpenny is the equivalent of pound sterling 2.5pence).

Usually walks around in fake designer clothes/clutching an imitation designer bag. Alternatively, they may have one genuine designer item with which they parade around with consistently. Can also apply to people who emphasise what they actually do have, or lie about what they have e.g. the size of their home/their earnings/the make of their car.
If being extremely stereotypical, it would be accurate to say that twopence ha'penny millionaires are usually insecure and rely on this behaviour to get attention or gain some credibility.

Girl 1: Ooooh, look at my new Louis Vuitton handbag, it cost £124930843025843
Girl 2: Hang on I swear you bought that out the back of that van in Turkey?
Girl 3: Yeah she did, she's not fooling anyone, she's just a twopence ha'penny millionaire

Twopence ha'penny millionaire by samaralic December 11, 2013