suborder osteostraci

NOUN
20 LETTERS · STARTS WITH S

suborder osteostraci is a valid 20-letter word worth 24 points in Scrabble and 27 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
S1U1B3O1R1D2E1R1O1S1T1E1O1S1T1R1A1C3I1
1 + 1 + 3 + 1 + 1 + 2 + 1 + 1 + 0 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 3 + 1 =24 PTS
DOUBLE WORD → 48TRIPLE WORD → 72
MEANING

What does suborder osteostraci mean?

NOUN · 1 SENSE
1

Extinct group of armored fish-like vertebrates; taxonomy is not clear.