"noisy drinking bout," 1735, from carouse (v.) + -al (2). The earlier noun was simply carouse "a drinking bout" (1550s).
Entries linking to carousal
carouse v.
"to drink freely and revel noisily," 1550s, from French carousser "drink, quaff, swill," from German gar aus "quite out," from gar austrinken; trink garaus "to drink up entirely." Kluge says it was originally the German exclamation accompanying closing time (Polizeistunde). From this it was generalized to "the end," especially in the phrase Den Garaus machen. The first element is from Old High German garo "ready, prepared, complete" (see gear (n.)); for the second element, see out (adv.). Frequently also as an adverb in early English usage (to drink carouse).
-al 2
suffix forming nouns of action from verbs, mostly from Latin and French, meaning "act of ______ing" (such as survival, referral), Middle English -aille, from French feminine singular -aille, from Latin -alia, neuter plural of adjective suffix -alis, also used in English as a noun suffix. Nativized in English and used with Germanic verbs (as in bestowal, betrothal).
row n.2
"noisy commotion," 1746, Cambridge student slang, of uncertain origin, perhaps related to rousel "drinking bout" (c. 1600), a shortened form of carousal. Klein suggests a back-formation from rouse (n.), mistaken as a plural (compare pea from pease).