Query re "tump"

[Rudolph C Troike]

To those less lexically impoverished by having this verb in your
vocabulary:

        I am wondering if dictionaries are right in labeling this "chiefly
Southern", and also if there are shades of meaning not captured in the
definitions. I have always assumed that this was simply part of everyone's
lexicon, until a colleague asked me about it recently and I checked a
couple of dictionaries.
        In asking my mother about it (now 98, from East Texas), she felt
that it contrasted with "dump" in either the degree of inclination of a
container, or in the size of the container, with "t" being less than "d"
in either case (a new consonantal ablaut?). Does anyone else share this
intuition?
        Origins seem obscure, but let me offer my own folk-etymology: a
combination of "tip" and "dump". It usually, but not necessarily, occurs
with "over".

        Rudy