My stomach is not "taunt". Even if it was tight it would be "taut".
The fact that my stomach is not "taut" gives reason for someone to "taunt" me.
If my stomach was "taut" not only could you not "taunt" me about it but I would "tout" it.
Now I can say that I "taught" you the differences between the words; "taut", "taunt" and "tout".
taught- to teach
taut- tight
taunt-tease
tout-promote