1469-Caller-Emma-Subtle by A Way with Words published on 2017-03-30T17:35:37Z Why don't we pronounce the letter b in the word subtle? The word derives ultimately from Latin subtilis, meaning "fine, delicate," and was adopted into Middle English from Old French as sotil. The b was later added back in so that the spelling reflected the word's original Latin roots, but the pronunciation continued to lack the b sound. http://waywordradio.org