- (idiomatic, dated) A melancholy mood accompanied by deep thought; a moody daydream.
1851, Herman Melville, Moby-Dick:
- So gathering up the shavings with another grin, and throwing them into the great stove in the middle of the room, he went about his business, and left me in a brown study.
- 1893, Arthur Conan Doyle, "The Adventure of the Cardboard Box":
- Finding that Holmes was too absorbed for conversation, I had tossed aside the barren paper, and leaning back in my chair, I fell into a brown study. Suddenly my companion's voice broke in upon my thoughts.
- 1978, Lawrence Durrell, Livia, Faber & Faber 1992 (Avignon Quintet), p. 428:
- But Quatrefages glared at his plate in a brown study.
Usually said as "somebody is in a brown study".