“In a brown study” is an old English idiom that means being lost in thought, often with a gloomy or melancholy tone. It does not refer to literally studying something brown.
The phrase is recorded from early modern English. In older usage, brown could suggest darkness, gloom, or melancholy. A study here means a state of meditation or absorbed thought. Put together, a brown study meant deep, dark, serious thinking.
Writers often used it for someone who seemed withdrawn or preoccupied. For example: After reading the letter, she fell into a brown study and said very little.
It helps to contrast this idiom with modern uses of study. Today, most people first think of schoolwork, but in this phrase the word means contemplation, not homework.
- Old sense: “study” = thought or meditation
- Old nuance of “brown”: gloom, darkness, melancholy
- Modern meaning: absorbed, often somber reflection
You will mostly meet this expression in older literature or deliberately literary modern writing, rather than in everyday conversation.