  We propose a new type of spin-valley locking (SVL), named $\textit{C}$-paired
SVL, in antiferromagnetic systems, which directly connects the spin/valley
space with the real space, and hence enables both static and dynamical controls
of spin and valley to realize a multifunctional antiferromagnetic material. The
new emergent quantum degree of freedom in the $\textit{C}$-paired SVL is
comprised of spin-polarized valleys related by a crystal symmetry instead of
the time-reversal symmetry. Thus, both spin and valley can be accessed by
simply breaking the corresponding crystal symmetry. Typically, one can use a
strain field to induce a large net valley polarization/magnetization and use a
charge current to generate a large noncollinear spin current. We predict the
realization of the $\textit{C}$-paired SVL in monolayer V$_2$Se$_2$O, which
indeed exhibits giant piezomagnetism and can generate a large transverse spin
current. Our findings provide unprecedented opportunities to integrate various
controls of spin and valley with nonvolatile information storage in a single
material, which is highly desirable for versatile fundamental research and
device applications.
