tertiary

باللغة العربية: ثالثي، من الدرجة الثالثة

1. Of third rank or order; subsequent.
2. Possessing some quality in the third degree; especially having been subjected to the substitution of three atoms or radicals. · a tertiary alcohol, amine, or salt
3. Of quills: growing on the innermost joint of a bird's wing; tertial.