“to shrink / to contract” in Japanese is 縮, read shuku, chiji (しゅく, ちぢ). It is a Grade 6 Kyōiku kanji, taught in year 6 of Japanese elementary school, and appears in words such as 縮小 (reduction).
What does 縮 mean?
セーターが縮む。
Same sound, different character — the classic trap. Compare them side by side: