Spin-lattice entanglement in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>CoPS</mml:mi> <mml:mn>3</mml:mn> </mml:msub> </mml:math>

The authors report here the most comprehensive study to date of the coupling between magnetism and the crystal lattice in CoPS${}_{3}$, a magnetic van der Waals material with high spin-orbit coupling and unquenched orbital moments. Employing a suite of experimental techniques, they uncover unambiguous signatures of spin-lattice coupling: magnetostriction and magnon-phonon hybridization. These findings illuminate the intricate interplay between the spin, orbital, and lattice degrees of freedom in this quasi-two-dimensional system.