Shortbow +3

Short Bow +3 is an enchanted weapon which has a speed factor of 3, weighs 2 lbs and it gives a -3 THACo bonus. This item appears in Baldur's Gate II: Throne of Bhaal and Baldur's Gate II: Enhanced Edition. It can be bought from the Tankard Tree and Karthis al-Hezzar.

In-game description
"Short bows were the first bows to be developed, although they were not called such. This is more of a default term that refers to anything which is not a long bow. Short bow staves are about 5 feet long on the average. This short bow is the rival of any of the larger bows. The magic inherent within it, whether from the wood or the spellcasting of a mage, makes this bow more accurate and damaging than a normal bow."