What do you call these?

[Thomas Winwood]

"OW".

[rickardspaghetti]

"Aj helvete! Jag stack mig!"

[Přemysl]

stickers/thistle

Prickers would be a kind of blackberry vine to me.

IMD prickers are bramble/blackberry. We do have something called stickers or burrs here but I'm not sure what plant they actually are. We call the one in the picture thistle, though when I was little I called them Eyores (big Winnie the Poo fan).

[tezcatlip0ca]

Thistle.

[Nannalu]

"Prickly cunt".

[kelemta]

A flowerless prickly thing in the grass is a "bindi" [bɪndi] or "bindi-eye" to most people I know (Western Australia), but the plant with a flower is a "thistle" if it's encountered. "Prickle" is also used pretty often for the flowerless nasties.

Not to be confused with "boondie" [bʊndi] — a rock, or a solid clump of sand/dirt. I gather both words are from Aboriginal languages.

[King of My Own Niche]

In all my life I have not heard that plant referred to by name.
Any name.
At all.
It's surprising how often that sort of thing happens in my experience.

[Gulliver]

Thistle, pronounced either thissl or fissou' depending on how drunk I am.

[Latinist13]

That plant I just call a weed. When doing work around outside, I always have to stamp them down... there are so many of those near my folks's rhubarb patch that I find them very annoying!

[marconatrix]

Thistle, pronounced either thissl or fissou' depending on how drunk I am.

Looks like a common thistle, that you get in lawns and meadows, about 15cm across, has small purple flowers on short stalks. What I think of as the Scottish Thistle is bigger, has the big bulbous flower in the later picture, and the flower stalk can be a metre tall or more. I think some people actually cultivate them.

Famous meditation on the (drunken) Scottish psyche :
http://myweb.tiscali.co.uk/epochmag/con ... stle1.html