"Do you understand?" or "
Do you comprehend".
The general usage of the term DIG as an indicator of understanding "do you dig" / "dig me" (as in "do you understand") comes from non-English speaking Irish immigrants in the USA speaking Irish to each other.
"An dtuigeann tú?" (pronounced "On digging two") means "Do you understand?".
Also used in a short form "dig it", "dig me" etc.
Used in the 50's by the
beatniks, the 60s and 70s saw it enter into the AAVE lexicon, the used of the term was widely popularised in
blacksploitation movies such as Shaft, and later movies such as "The Warriors".