godan verb (-ru), intransitive verb
shrink; become shorter; contract
Intransitive: the subject itself becomes smaller, shorter, or more contracted. Use 縮める for making something shorter or smaller deliberately.
セーターが洗濯で縮まった。
The sweater shrank in the wash.
寒さで体が縮まる。
My body curls up from the cold.
godan verb (-ru), intransitive verb
Used when a gap, difference, distance, or interval becomes smaller, such as a lead in a race or emotional distance between people.
トップとの差が少し縮まった。
The gap with the leader narrowed a little.
旅行の後、二人の距離が縮まった。
After the trip, the distance between the two of them grew smaller.