No, according to the reference provided, Brain is not a girl's name. It is a masculine name.
The name Brain is a respelling of the more common name Brian. According to The Bump, which is referenced in the search results, Brain is of Irish and Scottish origin and it means "high" or "noble". It is intended to match a baby's "thoughtful demeanor".
Here's a breakdown:
- Origin: Irish and Scottish.
- Meaning: "High" or "Noble".
- Gender: Masculine.
- Usage: A variant spelling of Brian.
Therefore, based on the provided reference, Brain is considered a masculine name and is not used as a girl's name.