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A fort is a stronghold and that’s what’s at the root of comfortable.
Comfortable is made up of three parts each of which comes to us via Old French and ultimately Latin. We’ll start at the end with –able. This suffix has a meaning of “likelihood,” so that something that is comfortable is likely to give comfort, someone who is agreeable is likely to agree, something that is stable is likely to stay or stand.
The com– in comfortable was once a con —but that didn’t mean “not” as in pros and cons, it is a prefix that intensifies the main meaning of the word. Con appears also in other words, so that confess literally means “intensely declare” and confide means “intensely trust.”
When comfort first appeared in English in 1225 it meant “encouragement” and “support”—and we still give each other comfort during trying times. So that the literal meaning of comfort makes sense; intensifying someone’s strength, their fortitude.
Our word for today, comfortable, appeared 200 years later and still held it’s meaning of giving moral support for 300 years or so until 1770 when it took on the more soft and cushy meaning that chairs and couches evoke.
Five days a week Charles Hodgson produces Podictionary – the podcast for word lovers, Thursday episodes here at OUPblog. He’s also the author of Carnal Knowledge – A Navel Gazer’s Dictionary of Anatomy, Etymology, and Trivia as well as the audio book Global Wording – The Fascinating Story of the Evolution of English.
I like the old meaning. The softer version doesn’t seem to work as well as it should. Now I see why. Will try a little less “tea & sympathy” and a bit more encouragement. It is to help someone out of their mental or physical state rather than to help them settle for it.
I came across the difference in a talk about the Holy Spirit, who has many titles/roles, one being The Comforter. This has been very helpful.