starboardside adjective 1adverb 1noun 1forms 3 adjective1 •On the starboard side.Said from where he landed he must have fallen from the starboardside ladder to the catwalk outside the wheelhouse. — 2000 adverb1 •Toward or on the starboard side.Ship was to dock portside to at pier 1 but ended up starboardside as docking became seriously complicated — 1959 noun1 •The starboard side of a boat. formsstarboardsides · more starboardside · most starboardside