1. Involving more than two parties

See also: many-sided, multilateral

• Umbellales
• umbellar
• umbellate
• umbellifer
• Umbelliferae
• umbelliferous
• umbelliferous plant
• umbelliform
• Umbellularia
• Umbellularia californica
• umber
• umbilical
• umbilical cord
• umbilical hernia
• umbilical vein
• umbilical vesicle
• umbilicate
• umbilicus
• umbles
• umbo
• umbra
• umbrage
• umbrageous
• umbrella
• umbrella arum