a. 倒齿状的

[ adj ]
having incised margins with the lobes or teeth pointing toward the base; as dandelion leaves
<adj.all>

Runcinate \Run"ci*nate\, a. [L. runcinatus, p. p. of runcinare
to plane off, fr. runcina a plane.] (Bot.)
Pinnately cut with the lobes pointing downwards, as the leaf
of the dandelion.