thiazine

noun Chemistry.

1. any of a class of compounds containing a ring composed of one atom each of sulfur and nitrogen and four atoms of carbon.

noun

1. any of a group of organic compounds containing a ring system composed of four carbon atoms, a sulphur atom, and a nitrogen atom

n.

1. Any of a class of organic chemical compounds containing a ring composed of one sulfur atom, one nitrogen atom, and four carbon atoms, used in making dyes.