1. Free from admixture with noxious elements; clean
   "unpolluted streams"
   - uncontaminated

See also: pure

• undefeated
• undefendable
• undefended
• undeferential
• undefiled
• undefinable
• undefined
• undelete
• undelineated
• undemanding
• undemocratic
• undemocratically
• undemonstrative
• undeniable
• undeniably
• undenominational
• undependability
• undependable
• undependableness
• undependably
• undepicted
• under
• under a cloud
• under arms
• under attack