Well, we’re going to keep this one short.
The rumor that orange doesn’t rhyme with any other word is (unfortunately?) incorrect. Orange rhymes with Blorenge (a mountain in Wales) and sporange (a technical word for a sac where spores are made). Of course, if you want to write a rhyming poem about oranges, the scientific or geographic research involved might be a little tough.
While we’re at it, while silver hangs on to the same rumor, it actually rhymes with Wilver (a nickname) and chilver (a ewe lamb).