Scat
mid 19th century: perhaps an abbreviation of scatter, or perhaps from the sound of a hiss (used to drive an animal away) + -cat .
wiktionary
From Middle English scet, schat, from Old English sceatt(“property, goods, owndom, wealth, treasure; payment, price, gift, bribe, tax, tribute, money, goods, reward, rent, a tithe; a piece of money, a coin; denarius, twentieth part of a shilling”) and Old Norse skattr(“wealth, treaure, tax, tribute, coin”); both from Proto-Germanic *skattaz(“cattle, kine, wealth, owndom, goods, hoard, treasure, geld, money”), from Proto-Indo-European *skatn-, *skat-(“to jump, skip, splash out”). Cognate with Scots scat(“tax, levy, charge, payment, bribe”), West Frisian skat(“treasure, darling”), Dutch schat(“treasure, hoard, darling, sweetheart”), German Schatz(“treasure, hoard, wealth, store, darling, sweetheart”), Swedish skatt(“treasure, tax, duty”), Icelandic skattur(“tax, tribute”), Latin scateō(“gush, team, bubble forth, abound”).
Origin uncertain. Both the Oxford English Dictionary [1] and Merriam-Webster [2] suggest derivation from Ancient Greek σκῶρ(skôr, “excrement”), compare English scato-, but Random House Dictionary suggests that the popular character of the word makes this unlikely. [3] Perhaps from English dialectal scat(“to scatter, fling, bespatter”), or an alteration of shit, which is also used for "drugs, heroin".
Probably imitative. [4]
From scoot, from the root of shoot. Alternatively, from the expression quicker than scat(“in a great hurry”), perhaps representing a hiss followed by the word cat. Compare Swedish schas(“shoo, begone”). (Can this(+) etymology be sourced?)
From the taxonomic name of the family
etymonline
scat (interj.)
"go away!" usually addressed to a small animal, 1838, via quicker than s'cat "in a great hurry," in which the word probably represents a hiss followed by the word cat.
scat (n.1)
"nonsense patter sung to jazz," 1926, probably of imitative origin, from one of the syllables used. As a verb, by 1935. Related: Scatting.
scat (n.2)
"filth, dung," by 1950, from Greek stem skat- "dung" (see scatology).
