Aleksandr is the Slavic form of Alexander, from Greek, meaning "defender of men."
Aleksandr is the East Slavic and Russian form of Alexander, tracing its lineage through Byzantine Greek to the ancient Macedonian Alexandros — a compound of 'alexein' (to defend) and 'aner/andros' (man), yielding the enduring meaning 'defender of men.' The name entered the Slavic world primarily through Christian Orthodox tradition and the towering influence of Alexander the Great, whose conquests from Greece to India made the name synonymous with military genius and imperial ambition across the ancient world. In Russia, the name took on its own sovereign weight: three Tsars bore it, most consequentially Alexander II, the reforming Tsar who emancipated the serfs in 1861 before being assassinated by revolutionaries in 1881.
The literary Aleksandrs of Russian culture alone could fill a library: Aleksandr Pushkin, whose poetry defined the modern Russian literary language and whose death in a duel at thirty-seven became a national wound; Aleksandr Blok, the Symbolist poet of the Silver Age; Aleksandr Solzhenitsyn, whose 'The Gulag Archipelago' documented Soviet state terror with the moral force of a biblical indictment. The name in Russian culture carries an almost inevitable expectation of greatness, which is perhaps why it has never fallen from favor. Outside Russia, Aleksandr (as opposed to the Anglicized Alexander) signals a deliberate connection to Slavic cultural heritage.
For parents of Russian, Ukrainian, Bulgarian, or Serbian background, this spelling is not an affectation but a homecoming — the name as it sounds in the language in which it carries its full history. Its nickname landscape is equally rich: Sasha, Sanya, Shura — a name that can be formal or deeply intimate depending on what you call it.