Thelma Ritter, character actress
Thelma "Pat" Nixon, First Lady
Thelma Todd, '30s star and murder victim
Thelma Wood, sculptor
Thelma Schoonmaker, American film editor of such films as Goodfellas, Raging Bull, The Aviator, The Departed, The Wolf of WallStreet etc.
Thelma from "Thelma and Louise"
Thelma Bloggs, character in SamuelBeckett's short stories "What a Misfortune" and "Draff" (from "More Pricks That Kicks," 1934); "fairly young person with expectations, Belacqua Shuah's second wife, dies on honeymoon"
Thelma Harper (aka Mama) from "Mama's Family"