abreast(s = adj.all) au courant, au fait, up on - being up to particular standard or level especially in being up to date in knowledge; "kept abreast of the latest developments"; "constant revision keeps the book au courant"; "always au fait on the latest events"; "up on the news"
abreast(r = adv.all) - alongside each other, facing in the same direction;
1. Side by side, with breasts in a line; as, “Two men could hardly walk abreast.” Macaulay. [1913 Webster]
2. Side by side; also, opposite; over against; on a line with the vessel's beam; -- with of. [1913 Webster]
3. Up to a certain level or line; equally advanced; as, to keep abreast of [or with] the present state of science. [1913 Webster]
4. At the same time; simultaneously. [1913 Webster]
"Abreast therewith began a convocation." [1913 Webster]
abreast, adv.
1 side by side and facing the same way.
2 a (often foll. by with) up to date. b (foll. by of) well-informed (abreast of all the changes).
Etymology:
ME f. A(2) + BREAST
N laterality, side, flank, quarter, lee, hand, cheek, jowl, jole, wing, profile, temple, parietes, loin, haunch, hip, beam, gable, gable end, broadside, lee side, points of the compass, East, Orient, Levant, West, orientation, lateral, sidelong, collateral, parietal, flanking, skirting, flanked, sideling, many sided, multilateral, bilateral, trilateral, quadrilateral, Eastern, orient, oriental, Levantine, Western, occidental, Hesperian, sideways, sidelong, broadside on, on one side, abreast, alongside, beside, aside, by the side of, side by side, cheek by jowl, to windward, to leeward, laterally, right and left, on her beam ends, his cheek the may of days outworn.