joco-serious

King James [VI and I] coming to Cambridge, vvas (amongſt others) entertained vvith a Philoſophy Act, and Mr. Brounrig [Ralph Brownrigg] vvas appointed to perform the Joco-ſerious part thereof, vvho did both to the vvonder of the Hearers.

a. 1662 (date written), Thomas Fuller, “Suffolk [Since the Reformation]”, in The History of the Worthies of England, London: […] J[ohn] G[rismond,] W[illiam] L[eybourne] and W[illiam] G[odbid], published 1662, →OCLC, page 61

Friendship, that wantonly admits / A joco-serious play of wits / In brilliant altercation, / Is union such, as indicates, / Like hand-in-hand insurance-plates, / Danger of conflagration.

1782 (date written), William Cowper, “On Friendship”, in William Hayley, The Life, and Posthumous Writings, of William Cowper, Esqr. […], volume I, Chichester, West Sussex: […] J[oseph?] Seagrave for J[oseph] Johnson, […], published 1803, →OCLC, stanza 16, page 217

Our proposed removal to Mr. Small's was, as you suppose, a jest, or rather a joco-serious matter. We never looked upon it as entirely feasible, yet we saw in it something so like practicability, that we did not esteem it altogether unworthy of our attention. It was one of those projects which people of lively imaginations play with, and admire for a few days, and then break in pieces.

1782 August 3 (date written), William Cowper, chapter VII, in Goldwin Smith, edited by John Morley, Cowper (English Men of Letters), New York, N.Y.: Harper & Brothers, […], published 1880, →OCLC, page 104