It can be a past tense of the verb "to see" or a tool used for cutting.
For example:
* I saw a bird in the tree. (past tense of "see")
* He used a saw to cut the wood. (tool)
It can be a past tense of the verb "to see" or a tool used for cutting.
For example:
* I saw a bird in the tree. (past tense of "see")
* He used a saw to cut the wood. (tool)