Tex. Insurance Code § 1952.103: UNDERINSURED MOTOR VEHICLE.

For purposes of the coverage required by this subchapter, "underinsured motor vehicle" means an insured motor vehicle on which there is collectible liability insurance coverage with limits of liability for the owner or operator that were originally lower than, or have been reduced by payment of claims arising from the same accident to, an amount less than the limit of liability stated in the underinsured coverage of the insured's policy.

Added by Acts 2005, 79th Leg., Ch. 727 (H.B. 2017), Sec. 2, eff. April 1, 2007.