A geriatric tramp stamp on the small of an elderly ladies back, that has morphed into an unrecognizable ink blob. Often confused with a bed sore, these markings can reach from her gooch to her hump back, depending on how rough a life she has lived.
Did you see the old chic JD was with last night... The ass crack had a giant butt blob.
by Jdbuttblob July 18, 2011
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