  Context: Luminosities of hot components in symbiotic binaries require
accretion rates that are higher than those that can be achieved via a standard
Bondi-Hoyle accretion. This implies that the wind mass transfer in symbiotic
binaries has to be more efficient.
  Aims: We suggest that the accretion rate onto the white dwarfs (WDs) in
S-type symbiotic binaries can be enhanced sufficiently by focusing the wind
from their slowly rotating normal giants towards the binary orbital plane.
  Methods: We applied the wind compression model to the stellar wind of slowly
rotating red giants in S-type symbiotic binaries.
  Results: Our analysis reveals that for typical terminal velocities of the
giant wind, 20 to 50 km/s, and measured rotational velocities between 6 and 10
km/s, the densities of the compressed wind at a typical distance of the
accretor from its donor correspond to the mass-loss rate, which can be a factor
of $\sim$10 higher than for the spherically symmetric wind. This allows the WD
to accrete at rates of $10^{-8} - 10^{-7}$ M(Sun)/year, and thus to power its
luminosity.
  Conclusions: We show that the high wind-mass-transfer efficiency in S-type
symbiotic stars can be caused by compression of the wind from their slowly
rotating normal giants, whereas in D-type symbiotic stars, the high mass
transfer ratio can be achieved via the gravitational focusing, which has
recently been suggested for very slow winds in Mira-type binaries.
