Anyone who learns English meets many odd words that contain silent letters, such as aisle, comb, debt, listen, rhythm, what, when, where, knock, sword, two . . . and many more.
One of the most intriguing is island with its silent s.
The Old English word was igland, from ig (meaning island) and land (meaning land).
And the Middle English word was iland, whose spelling is perfectly phonetic!
So . . . why was an s added to a perfectly phonetic spelling?
The Oxford English Dictionary reports that in the fifteenth century, the first syllable of iland began to be associated with ile (meaning island) in French, and the spelling sometimes changes to ile-land, combining the synonymous French and English words; and when ile was spelled isle, as it sometimes was in Old French, the compound became isle-land, which was later shortened to island, the accepted spelling since 1700.
So, the s in island was never pronounced, but persists in our spelling due to the influence of an older French form of ile.
* Orlando Bartro is the author of Toward Two Words, a comical & surreal novel about a man who finds yet another woman he never knew, usually available at Amazon for $4.91.