{s} having the same or almost the same meaning (as of a word); equivalent, expressing the same idea or intent
Having the character of a synonym; expressing the same thing; conveying the same, or approximately the same, idea
If you say that one thing is synonymous with another, you mean that the two things are very closely associated with each other so that one suggests the other or one cannot exist without the other. Paris has always been synonymous with elegance, luxury and style