noun
Refers to being punctual or happening at the scheduled time. Often used in business or event contexts.
会議はオンタイムで始まった。
The meeting started on time.
noun
work hours; time on duty
Used in contrast with オフタイム (off-duty time). Common in workplace or shift-work contexts.
オンタイム中は携帯電話の使用を控えてください。
Please refrain from using your mobile phone during work hours.
noun
Often considered incorrect usage; リアルタイム is the standard term. Still encountered in casual contexts for watching or experiencing something live.
See also: リアルタイム
その試合をオンタイムで見たかったけど、仕事で見られなかった。
I wanted to watch the game live, but I couldn't because of work.