slang for 'carabiner,' which is a piece of hardware used in rock climbing for clipping ropes, harnesses, webbing, etc.
*note* many people who climb in gyms buy carabiners that aren't real, and are stamped with the words "do not use for climbing, you will die." they then proceed to flaunt copious amounts of these keychains on backpacks, purses, water bottles, etc. while calling it a biner cos they think it sounds cool. they will often pronounce it "bine-er" due to being incompetent fools.
dude, i need a biner if i'm gonna belay you.
ooh, look at my biner! i climb at the ymca. i don't know what limestone is.
a word used to denote a small erect penis, used in a cute or whimsical fashion (smaller version of "boner")
Aww, Taylor has a biner, how cute!!
deragotory term for a Mexican
Them biners sure do put those roofs down fast!
Clipping device with many different uses in climbing. If you pay less than five dollars for one, you might as well just hang your keys from it. Although, if you are stupid enough to use a Home Depot "biner" to climb a route, more power to you and I'm sure it will hold you in a fall. I have come to realize, that the people who use the "biners" that they buy at Home Depot also tend to have harnesses made of rope and duct tape.
Check out all of my biners I got from Home Depot. What do you say to going out and leading El Capitan with me with all of these awesome biners.