William Bell Macdonald (1807–1862), was a Scottish linguist.
Macdonald, eldest son of Donald Macdonald, by Mary, daughter of William Bell of Rammerscales, near Lockerbie, Dumfriesshire, was born in Scotland in 1807, and was educated at the University of Glasgow, where he graduated B.A. 1827. After studying medicine he served as surgeon in Sir Pulteney Malcolm's flagship in the Mediterranean from 1828 to 1831, and was afterwards a commissioner of supply.
Macdonald was considered one of the greatest linguists of his time, making a special study of Coptic, and could translate an old Scottish song into German, Latin, Greek, or Hebrew.
On the death of an uncle named Bell he succeeded to the estate of Rammerscales, where he collected a large and valuable library. For some years he represented the burgh of Lochmaben in the general assembly of the church of Scotland.
In 1839, Macdonald married Helen, third daughter of Thomas Johnstone of Underwood. He died at 114 West Campbell Street, Glasgow, 5 Dec. 1862, and was buried in Dalton churchyard.
To the Ray Society in 1846 he communicated reports on zoology and botany translated from the German.