I. adverb 1. side by side and facing the same way • the path was wide enough for two people to walk abreast
• they were riding three abreast.
2. (usu. abreast of) — alongside or level with something • the cart came abreast of the Americans in their rickshaw.
3. up to date with the latest news, ideas, or information • keeping abreast of developments.
– origin late Middle English: from a-2 ‘in’ + breast.