An instrument whose top, back and/or Zargen have not been made of a single layer of tonewood (solid), but where several plies of different woods have been glued together. This helps savings costs (tonewoods are often expensive), but changes its tonal qualities. On the other hand, laminated woods do not crack as easily als massive woods. They are therefore better fit for journeys. Polemically, laminated wood is also called plywood.
Laminated wood doesn’t sound nearly as good as solid wood, but it is more durable. I would take a laminated ‘ukulele to the beach, I probably wouldn’t take a solid wood one.
Solid wood will unarguably give you the better sweeter sound, and in many cases better volume. Without getting too techy it's simply that the solid piece resonates and sings better than laminated wood.