1. Plutonium 239 that is recovered when nuclear weapons are disassembled; it is stored in plutonium pits
   - weapons plutonium

Type of: plutonium 239

• orangery
• orangewood
• orangish
• orangish-red
• orangutan
• orangutang
• Orasone
• orate
• oration
• orator
• oratorical
• oratorio
• oratory
• oratrix
• orb
• orb web
• orb-weaver
• orb-weaving
• orb-weaving spider
• orbicular
• orbiculate
• orbiculate leaf
• Orbignya
• Orbignya cohune
• Orbignya martiana