Thetis is a very rare girls' name that was most common in the 1910s and has all but disappeared.
Thetis is a girl name. It last appears in U.S. records in 1949. Thetis first appears in 1914 and peaked in 1915 (10 births).
| Year | U.S. births | U.S. + territories | Rank |
|---|---|---|---|
| 1949 | 6 | — | #5,205 |
| 1946 | 7 | — | #4,381 |
| 1941 | 5 | — | #5,021 |
| 1939 | 5 | — | #4,887 |
| 1933 | 5 | — | #4,793 |
| 1929 | 6 | — | #4,515 |
| 1928 | 9 | — | #3,416 |
| 1927 | 10 | — | #3,264 |
| 1925 | 8 | — | #3,997 |
| 1924 | 7 | — | #4,400 |
| 1923 | 10 | — | #3,336 |
| 1922 | 10 | — | #3,352 |
| 1921 | 5 | — | #5,784 |
| 1920 | 7 | — | #4,350 |
| 1919 | 8 | — | #3,774 |
| 1918 | 5 | — | #5,515 |
| 1917 | 8 | — | #3,678 |
| 1916 | 8 | — | #3,518 |
| 1915 | 10 | — | #2,881 |
| 1914 | 8 | — | #2,848 |