From WordNet (r) 2.0 (August 2003) [wn]:
koala
n : sluggish tailless Australian arboreal marsupial with gray
furry ears and coat; feeds on eucalyptus leaves and bark
[syn: koala bear, kangaroo bear, native bear,
Phascolarctos cinereus]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Koala \Ko*a"la\, n.
A tailless furry marsupial (Phascolarctos cinereus), found
in Australia. The female carries her young on the back of her
neck. Called also Australian bear, koala bear, {native
bear}, and native sloth. The koala lives almost all of its
life in trees, moves sluggishly like a sloth, and eats
eucalyptus leaves almost exclusively.
[1913 Webster +PJC] Kob