true blue

true, devoted, loyal; conservative

True Blue may refer to: True Blue (album), a 1986 album by MadonnaTrue Blue (TV series), a television drama airing 1989-1991True Blue (play), a 2005 play by Benjamin GeorgeTrue Blue: Oxford Boat Race Mutiny, a book by Dan Topolski and Patrick RobinsonTrue Blue (film), a 1996 film based on above bookTrueBlue, a brand of blueberry juiceTrueBlue, JetBlue's frequent flier loyalty program
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Adjective
1. marked by unswerving loyalty; "a true-blue American"; "a reliable true-blue country club conservative"
(similar) loyal

(n.)
A person of inflexible integrity or fidelity.
  

(a.)
Of inflexible honesty and fidelity; -- a term derived from the true, or Coventry, blue, formerly celebrated for its unchanging color. See True blue, under Blue.
  

loyal, faithful Moe is true blue. We've been good friends for forty years.