This is the 10098th most frequent Japanese word.
遣う
"遣う" means "to use," "to employ," or "to spend."
遣う is used here to mean 'spend' referring to the usage of time.
時間を遣うのが上手です。
He/she is skilled at spending time wisely.
遣う is employed to express 'consideration' or 'concern for others'.
彼は気を遣う人です。
He is a considerate person.
遣う refers to 'spend' focusing on the use of money.