Short for ad libitum. Means spontaneously, without prior practice or just unrestrained. Often refers to artists improvising, also known as "ad libbing", in other words playing from the top of their heads.
After the song was done they kinda started ad libbing into what seemed to be a whole new track, but was really just the guitarist fooling around.
Generally redundant improvised or unrehearsed lines that are frequently used in rap music.
examples of Ad-libs:
Lil Jon: Whaat? Okay! Yeaah!
Young Jeezy: Daaayum! Ayyyy! Thaaat's Riight!
Adding additional layers of vocal inflections over the existing main vocals in order to enhance the vocal effect of the song and also to add more variation and excitement to the vocal performance. When done properly a song can go from a grade of a mere C to an A+...........
Damn, did you hear Beyonce's Adlibs on that song. She blew down the house..........
While in the process of a song, the panning of your voice adding emphasis to phrases to empower your lyrics. Additional punchlines & etc.
"Dont ask me i'm just thinking out loud,(aaaaaaayyyyy!!!)
Purple haze got my head in the clouds." - Young Jeezy
Young Jeezy more/less popularized ad libs.
Vocal effects in music used and overdone by the likes of Lil' Jon and Young Jeezy
Young Jeezy: yeeeeeeeeeeeeeeeaaaaaaaa
Guy: lol adlib
Hack writing at its purest form.
With Ad-Libs, idiots can now make their own stupid book just by filling in the blanks.