The invention relates to a mechanical resonator having a tuning fork for a clock movement having a lever escapement, comprising a tuning-fork oscillator (1), at least one first arm (3) of which is to be oscillated on either side of a first axis and has at least one first pin combined with at least one first fork tooth of an anchor (10, 100) so as to pivot the latter between first and second angular positions, and alternately lock and release an escape wheel (24). The resonator comprises a conversion member (6, 7, 8, 15, 16) which is secured to the first pin and which is arranged to: convert the oscillations of the first arm (3) of the oscillator (1) into rotational movements of the anchor (10, 100) by transmitting first pulses to the latter; and transmit mechanical energy from the anchor (10, 100) to the first arm (3) of the oscillator (1) in the form of pulses such that the first tooth has an amplitude of movement that is either axial or substantially in the direction of the first axis during the pivoting of the anchor, said amplitude of movement being greater than the amplitude of movement of the first pin substantially in the direction of the first axis.