How is a musical transcription different from an arrangement?

In the context of musical performance, the terms "transcription" and "arrangement" are often used interchangeably, though they represent distinct approaches to adapting a composition.12

• Transcription is primarily the adaptation of a musical work for an instrument or ensemble other than the one for which it was originally written. The goal is typically to maintain the integrity of the original composition while making it accessible for a different medium.21
• Arrangement involves a similar process of adaptation but grants the arranger greater creative liberty. An arranger may feel free to embellish, simplify, or otherwise modify the original melody, harmonic structure, or instrumentation. In genres like jazz or rock, an arrangement often functions as a form of "improvisation on paper," where the arranger actively manipulates the original material to suit the specific group of musicians performing it.21

Historically, the distinction has shifted; while "transcription" once implied a more virtuosic elaboration of a work, modern usage often views arrangements as more subjective or transformative than transcriptions.1