From Longman Dictionary of Contemporary Englishload up on something phrasal verb American Englishto get a lot of something so that you are sure you will have enough SYN stock up (on) People were loading up on bottled water. → load→ See Verb table
Examples from the Corpus
load up on • But you needed a good depth of beer before you loaded up on the fancy stuff.• So load up on their stock.From Longman Business Dictionaryload up on something phrasal verb [transitive] journalism to buy a lot of somethingMore big investors are loading up on small stocks. → load→ See Verb table 