Here's a breakdown:
* Best: Indicates the highest quality, most suitable, or most appropriate.
* Describe: To explain or represent something in words.
Therefore, "best describe" implies choosing the words that most closely and effectively capture the essence of the subject being described.
Examples:
* "Which word best describes your mood today?"
* "The author uses vivid imagery to best describe the setting of the story."
* "I can't think of a word that best describes her unique sense of style."