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BaTiS₃ exhibits a hexagonal perovskite structure comprised of columns of sulphur coordinated Ti linked by barium making it a quasi-1D structure. Neutron pair distribution function measurements reveal that the Ti atomic displacement parameters increase with decreasing temperature. This observation suggest proximity to a ferroelectric type phase transition or, alternatively, dynamic disorder persisting in the ground state. A combination of phonon spectroscopy by inelastic x-ray scattering and inelastic neutron scattering supports the dynamic disorder scenario which extends into the quantum regime with Ti occupying a double-well potential. This unique dynamics have a profound consequence on the thermal conductivity and suggest a novel mechanism for thermal transport design.