Motion guide apparatus

A motion guide apparatus comprising:

• a track member including a rolling element rolling portion;
• a movable member including a loaded rolling element rolling portion facing the rolling element rolling portion of the track member, a return path parallel to a loaded path formed by the rolling element rolling portion and the loaded rolling element rolling portion, and a turn-around path connected to the loaded path and the return path;
• a plurality of rolling elements placed in the loaded path, the return path, and the turn-around path;
• and
• a retainer configured to hold at least one of the plurality of rolling elements, wherein
• a groove into which an end of the retainer in a width direction thereof enters is formed in the loaded path, the return path, and the turn-around path, and
• a width of the groove in at least a part of the turn-around path and the width of the groove in an entire length of the return path are greater than the width of the groove in at least a part of the loaded path.