Sneering

He turned to his orange juice sullenly, sneering that every little additive would sign him up for experiments he wanted no part in.

I never saw a circle of such hateful faces; and there was the man in the middle, with a kind of black sneering coolness — frightened too, I could see that — but carrying it off really like Satan.

Why are you sneering like that again?

He made a sneering comment about their closeness.