This is interesting. I got teased by my older sister a few years back for calling the man I was seeing boyfriend because he was 57.... she went so far as to say, isn't that kind of silly, he's not a "boy", so call him "mon petit chum"..... had to look it up, something like boyfriend but french. It irked me. I don't think age matters. But if I introduced him or he introduced me we were comfortable with boyfriend/girlfriend. Now that I think of it, and I have sometimes, I like "partner". But if someone says my significant other, I always assume that could mean they are gay/lesbian. Guess everyone's perspective is different.