They are in the sense that 100% transparency = 0% opacity. But in the end, aren't they both giving the same effect in CSS?
In Illustrator, for example, the interface has an opacity setting but the help file refers to it as setting the transparency since that is essentially what you're doing when you lower the opacity. (Personally, I prefer the word transparency, it just seems clearer to me.)
"I prefer the word transparency, it just seems..."
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In Illustrator, for example, the interface has an opacity setting but the help file refers to it as setting the transparency since that is essentially what you're doing when you lower the opacity. (Personally, I prefer the word transparency, it just seems clearer to me.)