1. Concave on both sides
   - biconcave

See also: concave

• intrude on
• intruder
• intruding
• intrusion
• intrusive
• intrusiveness
• intrust
• intubate
• intubation
• intuit
• intuition
• intuitional
• intuitionism
• intuitionist
• intuitive
• intuitive feeling
• intuitively
• intumesce
• intumescence
• intumescency
• intumescent
• intussuscept
• intussusception
• Inuit
• Inuktitut