From Longman Dictionary of Contemporary Englishtrade up phrasal verbBBTEXCHANGEto replace something you own with something better, or buy a better type of thing than before to/from It also encourages existing home owners to trade up to larger accommodation. → trade→ See Verb tableFrom Longman Business Dictionarytrade up phrasal verb [intransitive]MARKETING to buy more expensive goods that are of better qualityThousands of small-apartment owners are trading up for more luxurious accommodation. toHome-computer buyers are trading up to machines with more power and speed. → trade→ See Verb table