Si is a very rare name used for both girls and boys that was most common in the 2010s and has all but disappeared.
Si is predominantly a boy name. It last appears in U.S. records in 2017. Si first appears in 1927 and peaked in 2013 (15 births).
| Year | U.S. births | U.S. + territories | ♀ Rank | ♂ Rank |
|---|---|---|---|---|
| 2017 | 6 | 6 | — | #12,011 |
| 2014 | 5 | 5 | — | #13,762 |
| 2013 | 15 | 15 | — | #5,877 |
| 2012 | 8 | 8 | — | #9,575 |
| 2011 | 8 | 8 | #13,187 | — |
| 2010 | 5 | 5 | — | #13,955 |
| 2009 | 8 | 8 | — | #9,728 |
| 2007 | 10 | 10 | #20,131 | #14,083 |
| 2006 | 6 | 6 | #16,826 | — |
| 2004 | 7 | 7 | — | #9,787 |
| 2003 | 7 | 7 | — | #9,450 |
| 2001 | 5 | 5 | — | #12,051 |
| 1999 | 5 | 5 | — | #11,363 |
| 1998 | 8 | 8 | — | #7,443 |
| 1993 | 7 | — | — | #7,511 |
| 1989 | 9 | — | — | #5,532 |
| 1987 | 6 | — | — | #6,823 |
| 1982 | 5 | — | — | #7,227 |
| 1981 | 7 | — | — | #5,411 |
| 1980 | 11 | — | — | #3,811 |
| 1976 | 6 | — | — | #5,501 |
| 1972 | 8 | — | — | #3,920 |
| 1950 | 5 | — | — | #4,130 |
| 1942 | 5 | — | — | #3,975 |
| 1934 | 8 | — | — | #2,932 |
| 1927 | 5 | — | — | #4,709 |