An Etymological Dictionary of the German Language/Annotated/glimmen
glimmen, verb, ‘to shine dimly, glimmer,’ from Middle High German glimmen, strong verb, ‘to glow, glimmer,’ allied to Middle High German glamme, feminine, ‘glow,’ glim, ‘spark’ (Old High German *glimman); corresponding to Dutch glimmen; also Old High German gleimo, Middle High German gleime, ‘glowworm’ (whence the proper name Gleim), Middle High German glîmen, ‘to light, shine, Old Saxon glîmo, ‘gleam.’ To the Modern High German and Middle High German glimmern correspondent Anglo-Saxon *glimorian, English to glimmer, to which English gleam (Anglo-Saxon glœ̂m) is allied. The Old Teutonic root glimm, glī̆-m., contained in these cognates, is perhaps lengthened from a root glī̆ (compare Scandinavian gljá, ‘to shine’), with which Greek χλιαρός, ‘warm,’ χλιαένω, ‘to warm,’ as well as Irish gle (from the primary form gleivo-), ‘shining, clear,’ may be connected.