Steward or courtyard within castle walls
Bailyn is a modern American invention, likely created by combining the occupational surname Bailey with the popular 'lyn' suffix. Bailey derives from the Middle English 'baili', meaning a steward or public official, or from the Old French 'baile', referring to an outer castle wall.
Less common today
Bailyn isn't in the latest US Top 1000. It last peaked at #6,497 in 2011.
US births per 5-year period, 1990βpresent (SSA data).