Threeven

Analogous to even and odd, threeven means divisible by 3 and throdd means not divisible by 3. Kite Giedraitis has proposed the terms throdd-1 and throdd-2 for numbers that are 1 modulo 3 and 2 modulo 3 respectively.

These terms can be extended to fourven/fourodd, fiven/fivodd, etc.