“matter / thing” in Japanese is 事, read ji, zu, koto (じ, ず, こと). It is a Grade 3 Kyōiku kanji, taught in year 3 of Japanese elementary school, and appears in words such as 仕事 (work).
What does 事 mean?
今日は用事がある。
Same sound, different character — the classic trap. Compare them side by side: