1. Not easily solved
   "public finance...had long presented problems unsolvable or at least unsolved"
   - insolvable, unsoluble, unresolvable

See also: insoluble

• Maianthemum bifolium
• Maianthemum canadense
• maid
• maid of honor
• maid of honour
• maidan
• maiden
• maiden aunt
• maiden blue-eyed Mary
• maiden flight
• maiden name
• maiden over
• maiden pink
• maiden voyage
• maidenhair
• maidenhair berry
• maidenhair fern
• maidenhair spleenwort
• maidenhair tree
• objectivity
• objectless
• objector
• objet d'art
• objurgate
• objurgation