packrat

n. person who collects useless objects; person who never throws anything into the trash

For the fictional character, see Packrat (Transformers). A pack rat, also called a trade rat or wood rat, can be any of several species in the genus Neotoma, but most commonly the Bushy-tailed Woodrat (Neotoma cinerea).
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Noun
1. a collector of miscellaneous useless objects
(hypernym) collector, gatherer, accumulator
2. any of several bushy-tailed rodents of the genus Neotoma of western North America; hoards food and other objects
(synonym) pack rat, trade rat, bushytail woodrat, Neotoma cinerea
(hypernym) wood rat, wood-rat
(hyponym) dusky-footed woodrat, Neotoma fuscipes
(member-holonym) Neotoma, genus Neotoma