In short, the answer is NO, laminate flooring is NOT waterproof. There is a common misperception out there that laminate is waterproof, and I believe this is due to the fact that many customers mistakenly confuse vinyl and laminate flooring.
Many types of vinyl flooring are waterproof and/or highly water resistant. Laminate, on the other hand, is made out of recycled hardwood, so it is not waterproof. Due to its melamine wear layer, it has a tough finish which resists against scratches and may have minor protection against minor water (quick spills). But, like hardwood, laminate does not do well with standing water…regardless of whether this water is topical (on top) or seeping into the sub-floor from below. Laminate also does not do well in areas with high humidity.
There are some laminates that claim to be “splash proof” (which is not an industry term) and they do still warn you not to leave any standing water on your laminate floor). If laminate floors become really wet, they will get ruined and buckle. Unlike hardwood flooring, laminate floors can not be sanded or refinished. If they get wet, they can not be repaired. (Whereas if hardwood gets wet in a few spots, you can usually replace those planks and refinish the floors and they will look good as new.)
If you feel that hardwood is not a good option for an area due to water or humidity, it is also a good idea to avoid laminate.