nopal /nōˈpəl or -päl/

1. A Central American cactus of the genus Nopalea, used for rearing cochineal insects
2. Broadly, the prickly pear (genus Opuntia)

• optic
• Optic
• optical
• optical activity
• optical art
• optical character reader
• optical character readers
• optical character recognition
• optical computing
• optical disk
• optical disks
• optical-electronic device
• optical-electronic devices
• optical fibre
• optical fibres
• optical illusion
• optical illusions
• optically
• optical maser
• optical masers
• optical microscope
• optical pumping
• optical spectra
• optical spectrum
• optical splitter