Anent looks like a rather old-fashioned word, and it is, in fact, very old: an earlier sense of the word can be found in Beowulf, from approximately 800 C.E. Anent was at one point almost obsolete—it had nearly died out by the 17th century—but it was revived in the 19th century. Various usage commentators have decried anent as "affected" and "archaic." The former complaint seems like a harsh judgment, and the latter is untrue: although anent is rarely heard in speech, examples of current use can easily be found in written sources, especially in Scottish English. Once a favored preposition in Scots law, it turns up today in the occasional letter to the editor ("Anent your article on…"). Dead words do occasionally rise from the grave, and anent is one of them.
Word History
Etymology
Middle English onevent, anent, from Old English on efen alongside, from on + efen even