noun
materialist
Refers to a person who values material possessions and physical comfort over spiritual or intellectual values.
彼は物質主義者で、お金や物にしか興味がない。
He is a materialist, only interested in money and things.
物質主義 is the abstract concept of materialism, while 物質主義者 refers to a person who adheres to that philosophy.
Compound of 物質 (material) + 主義 (principle, -ism) + 者 (person).