Anu, just in case the "spear" thing is all still a mystery...
spear
noun [C]
1 a weapon consisting of a pole with a sharp, usually metal, point at one end, which is either thrown or held in the hand
2 a thin pointed stem or leaf:
asparagus spears
spear
verb [T]
1 to push or throw a spear into an animal:
They catch the fish by spearing them.
2 to catch something on the end of a pointed tool or object:
He speared a meatball with his fork.
AND
this meaning of "spare"
spare (EXTRA)
adjective
1 If something is spare, it is available to use because it is extra:
a spare key/tyre
spare sheets and blankets
Have you got a spare pen?
We've got a spare room if you want to stay overnight with us.
Could I have a word with you when you've got a spare moment/minute?
UK INFORMAL "Do you want this cake?" "Yes, if it's going spare (= if no one else wants it)."
2 spare time time when you are not working:
I like to do a bit of gardening in my spare time.
spare
noun [C]
1 an extra thing which is not being used and which can be used instead of a part which is broken, lost, etc.
2 a spare (part)
(from Cambridge Advanced Learner's Dictionary)
Online dictionaries can be handy: http://dictionary.cambridge.org/
:-)