Noun
An
unsaturated
hydrocarbon
,
C
<
sub
>
5
sub
>
H
<
sub
>
8
sub
>,
that
is
readily
polymerized
;
natural
rubber
(
caoutchouc
)
is
cis-1
,
4-polyisoprene
,
and
trans-1
,
4-polyisoprene
is
present
in
gutta-percha
and
balata
;
it
is
the
structural
basis
for
the
terpenes
.