Glennis is an uncommon name used for both girls and boys that was most common in the 1940s and has all but disappeared.
Glennis is predominantly a girl name. It last appears in U.S. records in 1997. Glennis was first reported in SSA data in 1912 and peaked in 1947 (62 births).
| Year | U.S. births | U.S. + territories | ♀ Rank | ♂ Rank |
|---|---|---|---|---|
| 1997 | 6 | — | #12,631 | — |
| 1993 | 5 | — | #14,274 | — |
| 1991 | 7 | — | #10,663 | — |
| 1989 | 11 | — | #7,136 | — |
| 1988 | 9 | — | #7,927 | — |
| 1987 | 9 | — | #7,574 | — |
| 1986 | 10 | — | #11,547 | #7,108 |
| 1985 | 6 | — | #9,713 | — |
| 1984 | 9 | — | #6,988 | — |
| 1983 | 5 | — | #10,830 | — |
| 1982 | 8 | — | #7,709 | — |
| 1980 | 11 | — | #10,914 | #5,784 |
| 1979 | 8 | — | #7,538 | — |
| 1978 | 11 | — | #8,905 | #6,143 |
| 1977 | 13 | — | #5,023 | — |
| 1976 | 9 | — | #6,220 | — |
| 1975 | 20 | — | #5,264 | #3,758 |
| 1974 | 8 | — | #6,440 | — |
| 1973 | 13 | — | #6,273 | #5,372 |
| 1972 | 15 | — | #6,151 | #4,151 |
| 1971 | 20 | — | #4,637 | #3,765 |
| 1970 | 20 | — | #3,926 | #4,998 |
| 1969 | 21 | — | #2,947 | — |
| 1968 | 26 | — | #3,222 | #2,978 |
| 1967 | 22 | — | #3,915 | #2,666 |
| 1966 | 24 | — | #3,187 | #3,081 |
| 1965 | 23 | — | #3,091 | #3,675 |
| 1964 | 46 | — | #1,712 | — |
| 1963 | 35 | — | #2,569 | #2,460 |
| 1962 | 32 | — | #2,965 | #2,219 |
| 1961 | 42 | — | #2,011 | #3,199 |
| 1960 | 38 | — | #2,465 | #2,254 |
| 1959 | 41 | — | #2,167 | #2,337 |
| 1958 | 29 | — | #3,282 | #2,125 |
| 1957 | 29 | — | #2,594 | #2,895 |
| 1956 | 53 | — | #2,120 | #1,550 |
| 1955 | 50 | — | #1,603 | #2,848 |
| 1954 | 54 | — | #1,632 | #2,073 |
| 1953 | 52 | — | #1,535 | #2,443 |
| 1952 | 40 | — | #1,954 | #2,194 |
| 1951 | 61 | — | #1,537 | #1,571 |
| 1950 | 59 | — | #1,438 | #1,772 |
| 1949 | 79 | — | #1,239 | #1,475 |
| 1948 | 61 | — | #1,555 | #1,472 |
| 1947 | 80 | — | #1,145 | #1,813 |
| 1946 | 51 | — | #1,426 | #2,073 |
| 1945 | 47 | — | #1,555 | #1,552 |
| 1944 | 56 | — | #1,263 | #1,768 |
| 1943 | 54 | — | #1,310 | #1,942 |
| 1942 | 57 | — | #1,197 | #2,081 |
| 1941 | 47 | — | #1,346 | #1,941 |
| 1940 | 57 | — | #1,123 | #1,835 |
| 1939 | 74 | — | #908 | #1,910 |
| 1938 | 72 | — | #996 | #1,497 |
| 1937 | 52 | — | #1,149 | #2,031 |
| 1936 | 68 | — | #923 | #1,994 |
| 1935 | 54 | — | #1,087 | #2,073 |
| 1934 | 41 | — | #1,384 | #2,062 |
| 1933 | 41 | — | #1,321 | #2,275 |
| 1932 | 49 | — | #1,403 | #1,612 |
| 1931 | 46 | — | #1,383 | #1,795 |
| 1930 | 45 | — | #1,185 | #4,222 |
| 1929 | 54 | — | #1,164 | #2,249 |
| 1928 | 57 | — | #1,140 | #2,442 |
| 1927 | 35 | — | #1,639 | #2,999 |
| 1926 | 48 | — | #1,315 | #2,476 |
| 1925 | 44 | — | #1,480 | #2,355 |
| 1924 | 49 | — | #1,233 | #3,636 |
| 1923 | 44 | — | #1,312 | #3,279 |
| 1922 | 48 | — | #1,238 | #3,363 |
| 1921 | 39 | — | #1,450 | #3,660 |
| 1920 | 33 | — | #1,565 | #4,561 |
| 1919 | 32 | — | #1,381 | — |
| 1918 | 29 | — | #1,660 | #4,420 |
| 1917 | 39 | — | #1,388 | #2,624 |
| 1916 | 30 | — | #1,647 | #3,023 |
| 1915 | 14 | — | #2,180 | — |
| 1914 | 13 | — | #1,951 | — |
| 1913 | 16 | — | #2,423 | #2,162 |
| 1912 | 12 | — | #1,656 | — |