Sentence:  The region, with its twenty-two hours of summer daylight, is now known for its giant vegetables that include six-foot-wide cauliflower, eighteen-pound carrots, fifty-pound celery, and the <WSD>granddaddy</WSD> of all giant vegetables, the Alaskan cabbage ... 
Meaning of the word marked with <WSD> tags:  Something that is the greatest or most significant of its kind.