  The moir\'e pattern observed in stacked non-commensurate crystal lattices,
such as hetero-bilayers of transition metal dichalcogenides, produces a
periodic modulation of their bandgap. Excitons subjected to this potential
landscape exhibit a band structure that gives rise to a quasi-particle dubbed
moir\'e exciton. In the case of MoS$_2$/WSe$_2$ hetero-bilayers, the moir\'e
trapping potential has honeycomb symmetry and, consequently, the moir\'e
exciton band structure is the same as that of a Dirac-Weyl fermion, whose mass
can be further tuned down to zero with a perpendicularly applied field. Here we
show that, analogously to other Dirac-like particles, moir\'e exciton exhibits
a trembling motion, also known as zitterbewegung, whose long timescales are
compatible with current experimental techniques for exciton dynamics. This
promotes the study of the dynamics of moir\'e excitons in van der Waals
heterostructures as an advantageous solid-state platform to probe
zitterbewegung, broadly tunable by gating and inter-layer twist angle.
