"Tomahawk" isn't further defined, but the general dictionary meaning which would probably be applied is a handheld axe (as opposed to a two-handed axe). The unpleasantly ambiguous aspect of this definition for me is the fact that "club" contains the phrase specifically designed, made, or adapted for use as a weapon. The courts in Texas have interpreted this through precedent to mean that a baseball bat is not a club, because it was not "specifically designed, made, or adapted" to beat someone with, but a piece of wood with some leather wrapped around it for a hand IS a club, because it was built specifically to use as a weapon, originally.Sec. 46.01. DEFINITIONS. In this chapter:
(1) "Club" means an instrument that is specially designed, made, or adapted for the purpose of inflicting serious bodily injury or death by striking a person with the instrument, and includes but is not limited to the following:
(A) blackjack;
(B) nightstick;
(C) mace;
(D) tomahawk.
If you buy a hatchet at Home Depot and happen to use it in self-defense, you can argue that it wasn't originally made as a weapon and therefore isn't a club, BUT, it might be inherently a "tomahawk", too, in the way that a "bowie knife" doesn't need to be longer than 5.5 inches to be an "illegal knife"; its inherent nature is defined as such. I've never found any court cases dealing with tomahawks, hatchets, or the like, so I wouldn't be willing to be the test case.
BTW, it might be moot for the reasons mentioned over at Texas Gun Talk - §46.02 doesn't apply to someone legally carrying a handgun and a LTC... the plain language of §46.15 would state that with a handgun and LTC, illegal knives and clubs can also be carried. It's a razor-dangerous argument, but yes, that guy in Austin was arrested for carrying an illegal knife along with his pistol and license, and he had the charges dismissed by what I assume was a very aggravated assistant district attorney who would've loved nothing more than to have slammed a guy who tried to push the envelope in Travis County. If the Travis DA's office won't accept charges for that interpretation, it's fairly safe to assume that that reading is correct, at least in practice if not in fact.