As proper nouns the difference between dec and doc
is that dec is an alternative spelling of Dec.|lang=en while Doc is a nickname for a medical doctor, a person with an advanced educational degree, or a learned person.
As an abbreviation dec
is declared.
As a noun doc is
a doctor.
As an initialism DOC is
drug of choice.
doc
English
Etymology 1
From by shortening.
Noun
(
en noun)
(informal) A doctor.
Etymology 2
From (document) by shortening.
Noun
(
en noun)
(informal) A document.
Usage notes
In professional jargon, this word is used especially in the plural to refer to technical documentation or collected legal evidence: "I'm not sure about that. I'll have to check the docs ."