A micromechanical sensor comprising a substrate (5) and at least one mass (6) which is situated on the substrate (5) and which moves relative to the substrate (5) is used to detect motions of the sensor due to an acceleration force and/or Coriolis force which occur(s). The mass (6) and the substrate (5) and/or two masses (5, 7) which move toward one another are connected by at least one bending spring device (6). The bending spring device (6) has a spring bar (9) and a meander (10), provided thereon, having a circle of curvature (K1; K6; K8; K9; K11) whose midpoint (MP1; MP6; MP8; MP9; MP11) and radius of curvature (r1; r6; r8; r9; r11) are inside the meander (10). For reducing stresses that occur, in addition to the radius of curvature (r1; r6; r8; r9; r11) having the inner midpoint (MP1; MP6; MP8; MP9; MP11), the meander (10) has at least one further radius of curvature (r2; r3; r4; r5; r7; r10) having a midpoint (MP2; MP3; MP4; MP5; MP7; MP10) outside the meander (10). The at least one further radius of curvature (r2; r3; r4; r5; r7; r10) is situated between the meander (10) and the spring bar (9).