Etymology From Latin instar (“form, likeness”), which is of obscure origin.
1
Any one of the several stages of postembryonic development which an arthropod undergoes, between molts, before it reaches sexual maturity.
2
An arthropod at a specified one of these stages of development.
In A. orientalis, first and second instars were more susceptible than third instars to H. bacteriophora TF strain, […]2005, Nematodes as biocontrol agents, edited by Parwinder S. Grewal, Ralf-Udo Ehlers, and David I. Shapiro-Ilan, (Please provide the book title or journal name), page 133:
3
Broadly A stage in development.
We avoided Tourist Homes, country cousins of Funeral ones, old-fashioned, genteel and showerless, with elaborate dressing tables in depressingly white-and-pink little bedrooms, and photographs of the landlady’s children in all their instars.1955, Vladimir Nabokov, Lolita, 1st American edition, New York, N.Y.: G[eorge] P[almer] Putnam’s Sons, published August 1958, →OCLC, part 2, page 148:
California spirituality is a late instar of America’s utopian impulse, and corporate meritocracy derives from the Whig dream of the self-made man that entranced young Abraham Lincoln.2014 January 8, Caleb Crain, “The Democratic Personality”, in The New Yorker:
instar
verb
UK /ɪnˈstɑː/ · US /ɪnˈstɑɹ/
Etymology From in- + star.
1
Archaic To stud or adorn with stars or other brilliants; to star.
Yet mark with shining steps the humbler way; And, as angelic feet instar the sky, Drop the bright sparks along the wilderness.1882, Frederick Randolph Abbe, The Temple Rebuilt: A Poem, page 125:
Espey could distinguish through the clear darkness the fringed branches of a pine-tree clinging to the heights above and waving against the instarred sky, and below a vague moving whiteness […]1893, The Atlantic Monthly, volume 72, page 507:
1 more example
He was dreaming, surely; or were those deep, instarred eyes really fixed upon him with that wistful gaze which he had seen only twice before?1896, Mary Noailles Murfree (pseudonym Charles Egbert Craddock), In the Tennessee mountains, 14th edition, page 209: