1. Incapable of being justified or explained
   - indefensible, insupportable, unwarrantable, unwarranted

See also: inexcusable, unjustifiably

• sunstone
• sunstroke
• sunstruck
• sunsuit
• suntan
• suntanned
• suntrap
• sunup
• sunward
• suo moto
• Suomi
• sup
• super
• super acid
• Super Bowl
• super C
• super heavyweight
• super-duper
• superable
• superabound
• superabundance
• superabundant
• superadd
• superaddition
• superannuate