Cuprous tellurides $\left({\mathrm{Cu}}_{2-x}\mathrm{Te}\right)$ have recently garnered attention due to their multiple commensurate charge density wave (CDW) transitions. To elucidate the nature of these phase transitions, we investigated single-crystalline ${\mathrm{Cu}}_{2-x}\mathrm{Te}$ $(x\sim 0.1)$ using temperature-dependent measurements of specific heat $\left(C_{\mathrm{P}}\right)$, electrical resistivity (ρ), Seebeck coefficient (S), and thermal conductivity (κ). Two distinct anomalies were identified, one near room temperature $\left(T_{\mathrm{CI}}\right)$ and another $\sim 150\mathrm{K}$ $\left(T_{\mathrm{CII}}\right)$, accompanied by thermal hysteresis, indicative of the first-order nature of these transitions. Metastable states that arise from the pinning of the CDW domain lead to irreversibility between $T_{\mathrm{CI}}$ and $T_{\mathrm{CII}}$ during cooling and warming, which is likely driven by intrinsic Cu vacancies and associated lattice strain. At $T_{\mathrm{CI}}$, a sharp $C_{\mathrm{P}}\left(T\right)$ peak with a modest entropy release signifies that the transition is primarily dominated by strong electron–phonon coupling and partial electronic condensation. In contrast, the weaker anomaly in $C_{\mathrm{P}}\left(T\right)$ at $T_{\mathrm{CII}}$ suggests predominantly lattice-driven dynamics, possibly involving a soft mode. The $\rho \left(T\right)$ data reveal electron-electron correlations at low temperatures and metal-to-metal-like CDW transitions, likely involving partial Fermi surface gapping. The S(T) displays multiple sign reversals and anomalous enhancements across both transitions, indicating complex multiband transport due to CDW-induced Fermi surface reconstruction. A marked suppression in κ(T) at $T_{\mathrm{CI}}$ with competing electronic and phononic effects provides further evidence of strong electron-phonon interactions. Additionally, a kink near $T_{\mathrm{CII}}$ supports the involvement of soft phonon modes and highlights the role of lattice dynamics. A comparative analysis with other CDW materials contextualizes these findings and emphasizes the potential of ${\mathrm{Cu}}_{2-x}\mathrm{Te}$ for thermoelectric applications.

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• Charge density waves
• Electrical properties
• Thermal conductivity
• 2-dimensional systems
• Thermoelectrics
• Resistivity measurements
• Specific heat measurements