You know, this is a place that might actually be able to provide a definitive answer to me.  A brief web search found me asking the same question in 1995.

When I were a wee lad, I was told `dd` was short for `do DEBE`, which, while obviously referencing a well-known movie about a Northern Texas sports team and their most enthusiastic fan, also referred to the mainframe software whose name was an acronym for `Does Everything But Eat` and whose function was to copy data across sources with very different blocking and representation conventions...which is kinda what `dd` does.

Can anyone here confirm or deny that origin for the utility's name?

Adam

On Sun, Sep 15, 2024 at 3:36 PM Larry McVoy <lm@mcvoy.com> wrote:

On Mon, Sep 16, 2024 at 08:15:34AM +1000, Rob Pike wrote:
> For me the fascinating thing about dd is that people tended to use the JCL
> notation for its arguments even after the Unix style was made available.
> That is, people prefer "dd if=foo" rather than "dd -if foo" or even the
> obviously easiest "dd <foo".

Muscle memory.  dd is weird but you sort of get used to it and then just
do it how you always have.