As nouns the difference between turbellarian and polyclad
is that turbellarian is (biology) any flatworm of the class turbellaria while polyclad is any member of the polycladida , a highly diverse clade of free-living marine turbellarian flatworms.
As an adjective turbellarian
is characteristic of these creatures.
polyclad
English
Noun
(
en noun)
Any member of the Polycladida , a highly diverse clade of free-living marine turbellarian flatworms.