A friend asked me today whether the words sublime and subliminal are etymologically connected. Well, that's a very interesting question with a fascination answer. First, sublime. Through Middle English sublimen and Old French sublimer, it traces to Latin sublimere, meaning "to raise high" (you sort of guess from there how both the meanings of "phase transition from solid to gas" and "exalted" can and did stem from this; the "lofty" definition has been around longer, though). The root here is limen, which meant threshhold, and the prefix is sub-, which in this case meant "up to". Subliminal also sprang directly from this exact combination, but how? Turns out that sub- can mean both "up to" and "below", although we know it more as being "below" in the English language. So something sublime is "up to" the threshold of what is good, while something subliminal sneaks in below the threshold of conscious thought. Sub-, through Proto-Italic, comes from PIE upo, "under", and limen is from Latin limus, which meant "oblique" and is of unknown origin
Adam Aleksic, a freshman studying linguistics at Harvard University, has been described as the internet's sixth most famous etymologist. He has disturbing interests in words, vexillology, geography, board games, limericks, and law, and he loves writing about himself in the third person.
The Etymology Nerd