A type of cataclysmic binary in which the magnetic field of the white-dwarf component is not strong enough to force the white dwarf to rotate synchronously (i.e. its rotation period is not the same as its orbital period); abbr. IP. Because the white dwarf does not rotate synchronously, the binary displays phenomena on a range of periods (including orbital, spin, and beat periods). Intermediate polars also differ from polars (AM Herculis stars) by the presence of an accretion disk in some cases, depending on the strength of the magnetic field. However, in all IPs magnetic effects dominate the mass transfer. The mass transfer predominantly occurs onto the polar caps of the white dwarf, via an accretion curtain from the inner edge of the accretion disk where such a disk exists, or via an accretion column if there is no disk. Almost all IPs emit hard X-rays, although the type star Nova Herculis 1934 (a famous slow nova) has the shortest known white-dwarf rotation period (71 s), and a magnetic field some 30 times less than that of a typical polar.