1. Fortitude and determination
   - backbone, grit, guts, moxie [N. Amer], sand, gumption 
2. [N. Amer, vulgar] A man's testicles

Type of: fortitude

Encyclopedia: Cojones

• on-license
• on-line database
• on-message
• on-off switch
• on-screen
• on-site
• on-street
• on-the-job
• on-the-scene
• onager
• Onagraceae
• onanism
• onanist
• once
• once again
• once and for all
• once in a blue moon
• once in a while
• once more
• once upon a time
• once-over
• onchocerciasis
• oncidium
• Oncidium papilio
• Oncidium papilio kramerianum