1. In a stealthy manner
   "stealthily they advanced upstream"

See also: stealthy

• orthophosphate
• orthophosphoric acid
• orthophosphorous acid
• orthopnea
• orthopraxy
• Orthopristis
• Orthopristis chrysopterus
• orthopter
• Orthoptera
• orthopteran
• orthopteron
• orthopterous insect
• orthoptic
• orthoptics
• orthoptist
• orthorhombic
• orthoscope
• orthoscopic
• orthostatic
• orthostatic hypotension
• orthotics
• Orthotomus
• Orthotomus sutorius
• orthotropic
• orthotropous