  Astrophysical jets seem to occur in nearly all types of accreting objects:
from supermassive black holes to young stellar objects. Based on X-ray
binaries, a unified scenario describing the disc/jet coupling has evolved and
extended to many accreting objects. The only major exceptions are thought to be
cataclysmic variables: Dwarf novae, weakly accreting white dwarfs, show similar
outburst behaviour as X-ray binaries but no jet has yet been detected. Here we
present radio observations of a dwarf nova in outburst showing variable
flat-spectrum radio emission that is best explained as synchrotron emission
originating in a transient jet. Both the inferred jet power and the relation to
the outburst cycle are analogous to those seen in X-ray binaries, suggesting
that the disc/jet coupling mechanism is ubiquitous.
