Pleasantry

[Sarah]

That which denotes or promotes pleasure or good humor;cheerfulness; gayety; merriment; especially, an agreeable playfulnessin conversation; a jocose or humorous remark; badinage.The grave abound in pleasantries, the dull in repartees and points ofwit. Addison.The keen observation and ironical pleasantry of a finished man of theworld. Macaulay.

[Agnes]

a polite and often slightly humorous remark, usually made to help other people feel relaxed:

[Sommer]

An inconsequential remark made as part of a polite conversation.