Definitions

1. verb

past tense of wind: to twist or turn something so that it is twisted or turned, especially a string or cord, around a central point

“The clock had to be carefully unwound before being repaired.”

2. adjective

twisted or turned around a central point

“The underwound spring in the toy caused it to malfunction.”

3. noun

a twisted or turned thread or cord, especially one that is the result of being wound up

“The underwound thread in the fabric caused it to fray quickly.”