urschleim n.

prefix meaning "original, earliest, primitive," from German ur- "out of, original," from Proto-Germanic *uz- "out," from PIE *ud- "up, out" (see out (adv.)) At first only in words borrowed from German (such as ursprache "hypothetical primitive language"); since mid-20c. a living prefix in English. Compare also Urschleim under protoplasm and Urquell under Pilsner.

"Any soft, ropy, glutinous, or viscous substance" [Century Dictionary], Old English slim "soft mud," from Proto-Germanic *slimaz (source also of Old Norse slim, Old Frisian slym, Dutch slijm "slime, phlegm," German Schleim "slime"), which is probably related to Old English lim "birdlime; sticky substance."

This is from a PIE root *(s)lei- "slimy, sticky, slippery" (source also of Sanskrit linati "sticks, stays, adheres to; slips into, disappears;" Russian slimak "snail;" Old Church Slavonic slina "spittle;" Old Irish sligim "to smear," leinam "I follow," literally "I stick to;" Welsh llyfn "smooth;" Greek leimax "snail," limne "marsh, pool, lake," alinein "to anoint, besmear;" Latin limus "slime, mud, mire," linere "to daub, besmear, rub out, erase").

As an insult to a person from mid-15c. Figuratively, of anything clinging and offensive, 1570s. Slime-mold, common name for a type of fungi, is from 1880.

"substance forming the essential stuff of the cells of plants and animals," 1848, from German Protoplasma (1846), used by German botanist Hugo von Mohl (1805-1872), on notion of "first-formed," from Greek prōtos "first" (see proto-) + plasma "something formed or molded" (see plasma).

The word was in Medieval Latin with a sense of "first created thing," and it might have existed in ecclesiastical Greek in a different sense. It was used 1839 by Czech physiologist Johannes Evangelista Purkinje (1787-1869) to denote the gelatinous fluid found in living tissue. The modern meaning is a refinement of this. This word prevailed, though German language purists preferred Urschleim. Related: Protoplasmal; protoplasmic.