| Thomas Whitten Slick | |
| Office: | Judge of the United States District Court for the Northern District of Indiana |
| Term Start: | April 21, 1928 |
| Term End: | September 16, 1943 |
| Appointer: | operation of law |
| Predecessor: | Seat established by 45 Stat. 437 |
| Successor: | Luther Merritt Swygert |
| Office1: | Judge of the United States District Court for the District of Indiana |
| Term Start1: | February 17, 1925 |
| Term End1: | April 21, 1928 |
| Appointer1: | Calvin Coolidge |
| Predecessor1: | Seat established by 43 Stat. 751 |
| Successor1: | Seat abolished |
| Birth Name: | Thomas Whitten Slick |
| Birth Date: | 5 July 1869 |
| Birth Place: | South Bend, Indiana |
| Education: | University of Michigan Law School (LL.B.) |
Thomas Whitten Slick (July 5, 1869 – January 3, 1959) was a United States district judge of the United States District Court for the District of Indiana and the United States District Court for the Northern District of Indiana.
Born in South Bend, Indiana, Slick received a Bachelor of Laws from the University of Michigan Law School in 1893. He was in private practice in South Bend from 1893 to 1925, serving as a prosecuting attorney of St. Joseph County, Indiana from 1896 to 1900 and as city attorney of South Bend from 1918 to 1922.
Slick was nominated by President Calvin Coolidge on February 6, 1925, to the United States District Court for the District of Indiana, to a new seat authorized by 43 Stat. 751. He was confirmed by the United States Senate on February 17, 1925, and received his commission the same day. Slick was reassigned by operation of law to the United States District Court for the Northern District of Indiana on April 21, 1928, to a new seat authorized by 45 Stat. 437. His service terminated on September 16, 1943, due to his retirement.
Slick died on January 3, 1959.