1. Unnecessary and unwarranted
   "a strikers' tent camp...was burned with needless loss of life"
   - gratuitous, uncalled-for

See also: needlessly, unnecessary, unneeded

• osculation
• osculator
• osculatory
• oscule
• osculum
• OSHA
• osier
• Osip Emilevich Mandelstam
• Osip Mandelstam
• Osiris
• Oslo
• Osman I
• Osmanli
• Osmanthus
• Osmanthus americanus
• Osmeridae
• Osmerus
• Osmerus eperlanus
• Osmerus mordax
• osmic
• osmiridium
• Osmitrol
• osmium
• osmolality
• osmolarity