The two adjectives describe two different approaches to examining a subject, such as ideas and concepts. The diachronic ('across time') approach examines the subject as it develops through time. The synchronic approach examines the subject as a whole without consideration for its various phases or varieties across the time that it took to develop. The diachronic approach provides us with a longitudinal view of the subject, while the synchronic approach provides us with a cross-sectional perspective.
©ALBERITH
u221020lch