1. Unplanned, informal, relaxed, or unexpected: When Mary and her friend were at the Farmers' Market, they had a casual meeting with her neighbor whom she had not expected to see there.
2. Designed for or concerning ordinary behavior, attire, etc.: The attitude and environment at the educational meeting was more casual than usual."
3. Characteristic of something being done without much thought, effort, or concern: Rosetta's daughter takes the most casual way of doing her assigned home work.
4. Regarding some interest in something, but not very much and not in a serious manner: Hayden has a casual interest in watching sports on TV.
5. A reference to something that happens at certain times, but not regularly: Helena does casual exercises at the fitness studio one in a while.