1. Done or happening at the appropriate or proper time
   - timely, seasonable, well timed

1. At an opportune time
   - seasonably, timely, apropos

See also: opportune

• 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
• oncogene
• oncologic