We report a ferroelectric field-effect transistor (FeFET) featuring two-dimensional (2D) semiconductor MoS₂, bi-directional sub-50 mV/dec subthreshold swing (SS), and ultra-large memory window (MW) of up to 11.5 V for high-accuracy (94.5%) 7-bit-state analog synapse. Our MoS₂-FeFET shows a small cycle-to-cycle (C2C) variation of MW, a high on-off ratio (~10⁷), extrapolated 10-year retention, and a record MW efficiency (η_v) of 200 %. The breakthrough of the coercive voltage limitation (2V_C) is attributed to the following factors: (i) by tuning the ratio of the dielectric area (A_OX) and the ferroelectric area (A_FE), we diminish the charge mismatch between dielectric and ferroelectric layers and the depolarization field in the gate stack; (ii) by adapting 2D MoS₂ as the channel material with dangling bond free surface, we achieve minimum trap density states at the interface; (iii) the hybrid contribution of the ferroelectric switching and the electron trapping/de-trapping in the ferroelectric layer.