Green’s Dictionary of Slang

1. extremely excited; a more extreme version is psyched to death.

1965		Lancaster New Era (PA) 12 Oct. 12/6: Teen-Age Vocabulary — You are ‘psyched up’ when something ‘turns you on’.
1970		Times 15 Sept. 6: I don’t believe in getting the crew all psyched up.
1972		Eble Campus Sl. Oct. 5: psyched out – in a high emotional state.
1984		C. White Life and Times of Little Richard 142: Thoroughly psyched up by this triumph, Richard went on to another ‘battle of the bands’.
1989		A. Sorkin A Few Good Men (1990) 102: Hey, I’m just psyched, brother, I’m juiced.
1993		M. Myers et al. Wayne’s World II [film script] Wayne: I’m so psyched for this concert.
2006		C. Hiaasen Nature Girl 145: I’m so psyched about tonight.
2012		C. Eble (ed.) UNC-CH Campus Sl. 2011 9: PSYCHED — excited in anticipation: ‘I’m so psyched about our trip to Hawaii.’.

2. emotionally ready.

1964		in Current Sl. (1967) I:4 4/2: Psyched up, adj. Prepared psychologically.
1974		H.L. Foster Playin’ the Dozens 248: [P]art of my psyching routine consisted of [...] clenching my fists, shutting my eyes, and saying something to myself like, ‘[. . . .] I am a man—I'm twenty-three years old—I'm a veteran—I will not take any more of their crap’.
1981		Eble Campus Sl. Mar. 5: psyched – [...] I’m psyched for this chemistry exam.
1997		N. Barlay Curvy Lovebox 37: He ain’t psyched up for backchat.
2009		T. Black Gutted 267: he was as psyched as a Formula One driver in the pits, raring to go.

3. very happy.

1997–2000

Da Bomb 🌐 23: Psyched: Very happy; ecstatic.

4. insane.

1967

M. Braly On the Yard (2002) 344: Now he’s psyched, a stone nut. They say he tried to take himself out. Cut his wrists, for Christ’s sake!