a small thin piece of steel, with a point at one end and a hole in the other, used for sewing [↪ pin]:
a needle and thread
a tapestry needle
a knitting needle
a very thin, pointed steel tube at the end of a syringe, which is pushed into your skin to put a drug or medicine into your body or to take out blood:
She carried hypodermic needles and syringes in her bag.
Drug users are at risk when they share needles.
a long thin piece of metal on a scientific instrument that moves backwards and forwards and points to numbers or directions:
a compass needle
a long, very thin piece of metal used in acupuncture (=a kind of medical treatment originally used in China)
a small needle-shaped leaf, especially from a pine tree:
the very small, pointed part in a record player that touches the record in order to play it
used to say that something is almost impossible to find:
Finding out which file you want can be like looking for a needle in a haystack.