On base is a commonly used term in sports, particularly in baseball. However, there are several synonyms that may be used to describe a player in terms of their positioning on the field. These include phrases such as "reached base," "got on base," and "got to first." Additionally, baseball commentators may use more casual language when describing a player on base, such as "he's standing over there at first," or "he's got his foot on the bag." Regardless of the specific phrasing, the underlying meaning is the same: the player has successfully reached a base and is in position to continue advancing around the field.