A literal translation is "my coconut sweet." (Disclaimer: I do not
speak or read Portuguese, but have had experience on Google Answers in
translating non-English words and phrases.)
"The Attack of the Killer B.....s!," by Bruce Gilman [scroll about 2/3
down the page to "Pelados em Santos"/"Naked in Santos", first verse]
As you can see in that song, it has a figurative meaning -- something
like referring to one's "sweetie." Another page compares it to the
expression in English, "honey pie."
"White Album (Beatles), Traduzido por Márcio Ribeiro (Creedance)"
[scroll about 2/3 down the page to "Honey Pie"/"Torta de Mel",
Search terms used, in various combinations, on Google:
"meu docinho de coco"
"docinho de coco"
[I found English words that correspond to the Portuguese words through
tools in the Google Directory's Portuguese category: