Definitely a rooster. He has Sickle, Saddle, and Hackle feathers. Some Cocks/cockerels have no spurs. Or very little spurs. And some hens have huge spurs to. Only cockerels and cocks have Saddle and Sickle feathers. Hens can have hackle feathers, but they will be rounded. Cockerels will have pointy Hackle feathers. As others said, he is just late to mature.
