bow saw

from The American Heritage® Dictionary of the English Language, 4th Edition

• n. A saw with a slender blade connected at each end to a narrow handle that curves outward like an archer's bow.

from Wiktionary, Creative Commons Attribution/Share-Alike License

• n. A lightweight metal-framed saw in the shape of a bow with a removable coarse wide blade, used for cutting tree trunks.
• n. A woodworking saw used for straight or curved cuts.