“Party down”

“Party down” means to celebrate with great enthusiasm. “Party Down” (1974) by Willie “Little Beaver” Hale and “Party Down” (1975) by Willie Hutch are soul songs that popularized the saying.
 
Other “party” phrases include “party hearty” and “party on.”
 
 
Dictionary.com
party hearty definition
and party down
in.
to have a great time; to celebrate
 
(Oxford English Dictionary)
party, v.
intr. colloq. (orig. and chiefly U.S.). to party down: to go to parties, celebrate, drink, etc., esp. unrestrainedly. Freq. in imper. Cf. party-down adj.
1976 New Yorker 27 Sept. 27/3   Let’s party down.
1987 R. McCammon Swan Song ii. vi. 64   Party down! he thought, and he giggled with a noise like grinding glass.
2000 R. Barger et al. Hell’s Angel xv. 254   After partying down with the Zurich chapter we hit the winding European highways on Harley full dressers.
party-down, adj.
Characterized by frequent and unrestrained partying, including the consumption of alcohol or illicit drugs.
1979 L. Bangs in Village Voice (N.Y.) 30 Apr. 46/1   Things like the Creem articles and partydown exhibitionism represented a reaction against the hippie counterculture.
1994 Guardian (Nexis) 12 Aug. 18   It is the greatest three-week, booze-up, party-down, event in all of Europe.
 
OCLC WorldCat record
Party down. / Part 1 ; Part down. Part 2
Author: Little Beaver.
Publisher: [S.l.] : Cat, [between 1972 and 1976]
Edition/Format:   Music : 45 rpm : Popular music : English
 
Google Books
17 August 1974, Billboard magazine, “Billboard Hot Soul Singles,” pg. 30, col. 4:
95. PARTY DOWN-Little Beaver
 
OCLC WorldCat record
Party down
Author: Willie “Little Beaver” Hale
Publisher: President, p 1975.
Edition/Format:   Music
 
OCLC WorldCat record
Party down
Author: Willie Hutch; F Hutch
Publisher: [Hollywood, Calif.] : Motown, 1975.
Edition/Format:   Music : 45 rpm : Popular music : English
 
Google Books
... And the Hits Just Keep on Comin’
By Peter E. Berry
Syracuse, NY: Syracuse University Press
1977
Pg. 127:
Disco music was widely diversified and not a redundant clamor underneath a crystal ball: the common denominator was danceability, and its motivating spirit was the public’s desire to, in the words of Willie Hutch, “Party Down.”
 
OCLC WorldCat record
Party down Do you think about it
Author: Nazareth (Grup musical)
Publisher: Madrid : Fonogram, DL 1984.
Edition/Format:   Music : 45 rpm : English
 
OCLC WorldCat record
Party down : from the Paramount motion picture “Witness”
Author: Scott Shelly; Alan Brackett
Publisher: Hialeah, Fla. : Columbia Pictures Publications, ©1985.
Edition/Format:   Musical score : English