During the context of art heritage, modernity (modernité) has a more constrained sense, modern art masking the period of c. 1860–1970. Use in the time period in this feeling is attributed to Charles Baudelaire, who in his 1863 essay "The Painter of Modern Life", specified the "fleeting, ephemeral practical experience https://thesocialdelight.com/story2303193/detailed-notes-on-culture-of-the-united-states