Definition of "serene"

Serene, smiling, enigmatic, she faced him with no fear whatever showing in her dark eyes. The clear light of the bright autumn morning had no terrors for youth and health like hers.

1910, Emerson Hough, “A Lady in Company”, in The Purchase Price: Or The Cause of Compromise, Indianapolis, Ind.: The Bobbs-Merrill Company, page 6

Now ſleeping flocks on their ſoft fleeces lie, / The moon, ſerene in glory, mounts the sky, […]

1717, Alexander Pope, “Winter. The Fourth Pastoral. […]”, in The Works of Mr. Alexander Pope, volume I, London: […] W[illiam] Bowyer, for Bernard Lintot, […], page 30

Full many a gem of pureſt ray ſerene / The dark unfathom'd caves of ocean bear: […]

1750 June 12 (date written; published 1751), T[homas] Gray, “Elegy Written in a Country Churchyard”, in Designs by Mr. R[ichard] Bentley, for Six Poems by Mr. T. Gray, London: […] R[obert] Dodsley, […], published 1753, page 32

A serene sky and verdant fields filled me with ecstasy.

1818, [Mary Shelley], chapter VI, in Frankenstein; or, The Modern Prometheus. […], volumes (please specify |volume=I to III), London: […] [Macdonald and Son] for Lackington, Hughes, Harding, Mavor, & Jones

The Hoary Froſts, and Northern Blaſts take care / Thy muddy Bev'rage to ſerene, and drive / Præcipitant the baſer, ropy Lees.

1708, [John Philips], “Book II”, in Cyder. […], London: […] J[acob] Tonson, […], page 68

When heaven and earth, as if contending, vye / To raiſe his being, and ſerene his ſoul.

1728, James Thomson, “Spring”, in The Seasons, London: […] A[ndrew] Millar, and sold by Thomas Cadell, […], published 1768, page 34, lines 866–867

the serene of heaven

1801, Robert Southey, “(please specify the page)”, in Thalaba the Destroyer, volumes (please specify |volume=I or II), London: […] [F]or T[homas] N[orton] Longman and O[wen] Rees, […], by Biggs and Cottle, […]

To their master is denied / To share their sweet serene.

1742, Edward Young, Night Thoughts on Life, Death and Immortality

Some serene blast me.

1605 (first performance), Benjamin Jonson [i.e., Ben Jonson], “Volpone, or The Foxe. A Comœdie. […]”, in The Workes of Ben Jonson (First Folio), London: […] Will[iam] Stansby, published 1616