from The American Heritage® Dictionary of the English Language, 4th Edition
- suffix Having a specified kind or number of parts: isomerous.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- suffix Having parts of the specified quality.
- suffix Comprising the specified number of parts.
From New Latin -merus, from Greek -meros, from meros, part; see (s)mer-2 in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
From the suffixation of the French -mère and its etymon the Ancient Greek -μερής (-merēs) (“having (the specified number of) parts”, “sharing”: the combining form of μέρος (meros, "part")) with the English -ous; compare the English -mer and -mere, as well as the French -mère and the German -mer. (Wiktionary)