What does Def mean? There is Def Leppard, Mos Def, Def Jam. Is there one meaning? Are there more Defs?

In the case of Def leppard:

"Soon afterward they adopted a name proposed by Elliott, "Deaf Leopard", which was originally a band name he thought up while writing reviews for imaginary rock bands in his English class [5] At Kenning's suggestion, the spelling was slightly modified in order to make the name seem less like that of a punk band."

https://en.wikipedia.org/wiki/Def_Leppard

Def -- Slang
Excellent; first-rate.

http://www.ask.com/web?q=dictionary%3A+def&content=ahdict%7C62225&o=14824&l=dir

The word def is hip hop (including graffiti) slang for 'great', 'ill', 'dope', 'fly': generally, a positive adjective used as a superlative. Taken from the root word 'definitive', if something is 'def' then it is classified as being very good. If something is very definitive in its representation of its genre or classification, it is 'def'. Def Jam records took their name from this term.

https://en.wikipedia.org/wiki/Def

DEF, the acronym
Mos Def: a rap artist.
Def Jef: a rap artist
So So Def Recordings: a rap record label.
Def Jam Recordings: a rap record label.
Def American: a rock and rap record label.
Def Pen Radio: an online radio show.
Def Leppard: British hard rock band.
Deftones: an American alternative rock band from Sacramento, California
DefEntertainment.com: a free rap, hip-hop, R&B and reggae web portal
Def Mix Productions: Frankie Knuckles' primary business venture
Def: an alternate spelling of Daf, a MidEastern frame drum.
Def: To describe something extremely shocking or unbelievably unfortunate.

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