Free man or beloved lake
A modern American blend likely combining the Germanic name Kara or Karen with the popular suffix -lyn. It can be interpreted as a variation of Caroline, meaning 'free man', or a combination of Kari and Lynn, suggesting 'beloved lake'.
Less common today
Karilyn isn't in the latest US Top 1000. It last peaked at #5,612 in 1990.
US births per 5-year period, 1990βpresent (SSA data).