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Crystals of the rare earth metal polytelluride LaTe1.82(1), namely, lanthanum telluride (1/1.8), have been grown by molten alkali halide flux reactions and vapour-assisted crystallization with iodine. The two-dimensionally incommensurately modulated crystal structure has been investigated by X-ray diffraction experiments. In contrast to the tetragonal average structure with unit-cell dimensions ofa= 4.4996 (5) andc= 9.179 (1) Å at 296 (1) K, which was solved and refined in the space groupP4/nmm(No. 129), the satellite reflections are not compatible with a tetragonal symmetry but enforce a symmetry reduction. Possible space groups have been derived by group–subgroup relationships and by consideration of previous reports on similar rare earth metal polychalcogenide structures. Two structural models in the orthorhombic superspace group,i.e.Pmmn(α,β,1 \over 2)000(−α,β,1 \over 2)000 (No. 59.2.51.39) andPm21n(α,β,1 \over 2)000(−α,β,1 \over 2)000 (No. 31.2.51.35), with modulation wave vectorsq1 = αa* + βb* + 1 \over 2c* andq2= −αa* + βb* + 1 \over 2c* [α = 0.272 (1) and β = 0.314 (1)], have been established and evaluated against each other. The modulation describes the distribution of defects in the planar [Te] layer, coupled to a displacive modulation due to the formation of different Te anions. The bonding situation in the planar [Te] layer and the different Te anion species have been investigated by density functional theory (DFT) methods and an electron localizability indicator (ELI-D)-based bonding analysis on three different approximants. The temperature-dependent electrical resistance revealed a semiconducting behaviour with an estimated band gap of 0.17 eV.