Definify.com
Webster 1913 Edition
Botryoidal
{ 
Bot′ry-oid
,Botˊry-oid′al
, }Adj.
 [Gr. 
[GREEK] 
cluster of grapes + -oid
.] Having the form of a bunch of grapes; like a cluster of grapes, as a mineral presenting an aggregation of small spherical or spheroidal prominences; 
as, 
.botryoidal 
hematite
Syn. – botryose.