noiselessly
noiselessly — adverb
1. in a way that produces no sound; with complete quiet during movement, operation,
in a way that produces no sound; with complete quiet during movement, operation, or action
Felix's new vacuum cleaner moved noiselessly across the living-room floor.
verb of motion + noiselessly
Takeshi slipped noiselessly past the sleeping patients' beds in the hospital ward.
Aarav's laptop fan ran completely noiselessly even during long video calls.
The dishwasher in apartment 3B ran noiselessly through the whole cleaning cycle.
The old grandfather clock in the hallway ticked noiselessly before it finally stopped.
- silently
more common in everyday English; preferred in most ordinary contexts
- quietly
broader meaning — can mean low volume rather than complete silence
- soundlessly
more literary or technical; emphasises absence of any audible sound
用法筆記
Commonly describes mechanical equipment (fans, motors, appliances) or stealthy movement (animals, people, vehicles). More literary than the everyday word 'silently'.