資 or 자 in hangul means "property" or "funds". It is used as a root in the following words:

투자 投資 (throw-funds) : investment
자본 資本 (funds-source) : capital (자본주의: capitalism)
융자 融資 (blend-funds) : financing
자원 資源 (funds-origin) : natural resources
자료 資料 (funds-material) : data, study material