There is no meaning for the acronym LAWD. Lawd is however, a southern drawl version of saying "Lord."
Lawd A Massi is common phrase in Jamaican English (Patois) that is used a lot in Reggae music and has veered away from its original meaning: Lord, Have Mercy.
See A-Z of Jamaican Patois (Patwah): Words, Phrases and how we use them by Teresa P. Blair, Ph.D.
See literary works referencing to the Lawd as a variant of saying Lord here.
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