An inadequate singer, comedian, or other live performer who lacks the talent to succeed in a reputable market or venue, and is thus relegated to doing their act on boats and/or cruise ships. Audiences typically consist of uncultured tourists, addictive gamblers, and the elderly.

(One step below "lounge act.")
Despite being a complete BOAT ACT, Dat Phan somehow won "Last Comic Standing."
by RnFDoctorZ February 12, 2009
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