A meeting in which members gather for religious instruction outside of regular Sunday meetings. Firesides generally focus on a particular group or topic, such as youth, or missionary work.
A fireside is a supplementary, evening meeting in The Church of Jesus Christ of Latter-day Saints. They are usually held for a subset of members (youth, YSA, Single Adult, etc.) of a congregation or congregations in an area. A fireside is most commonly held on Sunday evenings, but may be held on any day of the week.