In this particular context, 'abreast' refers to the position of being parallel or at equal level with something or someone, especially when moving forward. It indicates the arrangement or placement of individuals or objects in a line or row on the same level, directly adjacent, alongside or next to one another. It is often used to represent equal progress or advancement alongside or synchronously with others, or to indicate simultaneous understanding or knowledge of information or events.

1. The soldiers marched down the street four abreast, impressing the crowds with their precision and synchrony. 2. At the marathon, the top runners kept abreast for the majority of the race, testing each other's endurance and speed. 3. The two friends walked abreast down the beach, enjoying their conversation and the beautiful sunset. 4. The ships sailed abreast through the night, maintaining a steady formation to avoid collision. 5. The two cyclists stayed abreast during the journey, ensuring that each of them had the same view of the wilderness.

In the context of sailing, the term 'abreast' is used to describe two ships that are sailing side by side. Interestingly, sailors back in the days came up with the term from a combination of "a" which means "on" in old English and "breast" symbolizing the chest or front of something. Thus, going "abreast" is like two sailors standing shoulder to shoulder, facing in the same direction. Besides displaying unity, ships sailing 'abreast' also portrayed power and equality, often associated with naval fleet formations. What began as a nautical term eventually found its usage in general context meaning side by side.