what is its modern definition?
The question of defining a precise eastern boundary of Europe arises in the Early Modern period, as the eastern extension of Muscovy began to include North Asia.
Europe
The question of defining a precise eastern boundary of Europe arises in the Early Modern period, as the eastern extension of Muscovy began to include North Asia. 
where does the flesh of an apple come from Central Asia what is apple? It is an edible fruit produced by an apple tree. how is it related to paganism in germany? English scholar H. R. Ellis Davidson links it to religious practices in Germanic paganism. what is its maturation time? The fruit matures in late summer or autumn, and cultivars exist in a wide range of sizes. what are its usages? All parts of the fruit, including the skin, except for the seeds, are suitable for human consumption. what is its importance in the mythology of the greeks? The Greek goddess of discord, Eris, became disgruntled after she was excluded from the wedding of Peleus and Thetis. In retaliation, she tossed a golden apple inscribed Καλλίστη into the wedding party. what is known about the first mentioned goddess? She is the Greek goddess of discord. where is the aforesaid fruit found? Asia and Europe. what is the latter mentioned place? A continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere.
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Europe [SEP] Modern definitions
The question of defining a precise eastern boundary of Europe arises in the Early Modern period, as the eastern extension of Muscovy began to include North Asia. Throughout the Middle Ages and into the 18th century, the traditional division of the landmass of Eurasia into two continents, Europe and Asia, followed Ptolemy, with the boundary following the Turkish Straits, the Black Sea, the Kerch Strait, the Sea of Azov and the Don (ancient Tanais). But maps produced during the 16th to 18th centuries tended to differ in how to continue the boundary beyond the Don bend at Kalach-na-Donu (where it is closest to the Volga, now joined with it by the Volga–Don Canal), into territory not described in any detail by the ancient geographers.