Enter a clue or pattern or both:
The Clue
Roman 905 (3 letter answer)
The Answer
CMV
Tags
Notes
The answer CMV is so rare that it appears less than once every 2500 puzzles.
Definition
CMV as a noun:
1. (cytomegalovirus, CMV) = any of a group of herpes viruses that enlarge epithelial cells and can cause birth defects; can affect humans with impaired immunological systems