Which musical term means 'weighty' or 'with emphasis'?

The term that signifies 'weighty' or 'with emphasis' in a musical context is pesante. This term is used to instruct musicians to play in a manner that conveys heaviness and a strong emphasis on the notes, often resulting in a slower and more deliberate articulation. It evokes a sense of gravity in the performance, setting it apart from other dynamics that might instruct a lighter or more gentle touch.

In contrast, the other terms do not convey this sense of weightiness. Morendo typically refers to a fading or dying away, suggesting a gentle decrescendo rather than emphasis. Mezzo piano indicates a moderate soft dynamic, implying a quieter sound instead of one with emphasis. Mezzo forte denotes a moderately loud dynamic, which certainly has volume but lacks the specific connotation of weight or gravity that pesante carries. Thus, pesante is uniquely suited to describe the desired musical quality of heaviness and emphasis.