Lennyn has been given to about 930 people in the United States since 1880. It was most common in 2025, which makes it a current name.
Its best year was 2025, when 142 babies were given the name, ranking 1552nd. The typical living American called Lennyn is about 5 years old today. It is relatively most common in South Dakota, where it accounts for 0.09% of births.
Source: US Social Security Administration, national and state name files, 2025 release. Etymology researched and written by our editors. Living-population and median-age figures are our own estimates, described in the methodology.