E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Loblolly Boy (A.)
A surgeons mate in the navy. Here lob is the Welsh llob, a dolt, and loblolly boy is a dolt not yet out of his spoon-meat or baby-pap.
1
Loblolly-boy is a person on board a man-of-war who attends the surgeon and his mates, but knows as much about the business of a seaman as the author of this poem.The Patent (1776).