Old silurian Synonyms

We can't find synonyms for the phrase "Old silurian", but we have synonyms for terms, you can combine them.

Old Synonyms

Silurian Synonyms

OS abbreviation

OS is an abbreviation for Old Silurian
What does OS stand for?
OS stands for "Old Silurian"

Definitions for Old


  • (adjective) being of advanced years and especially past middle age
  • (adjective) dating or surviving from the distant past
  • (adjective) having been such at some previous time

Definitions for Silurian


  • (noun) from 425 million to 405 million years ago; first air-breathing animals