noun
Refers to a seam that has come apart, or a small tear in fabric. Often used literally for clothing or metaphorically for cracks in relationships or plans.
スカートの綻びを縫ってもらった。
I had the open seam on my skirt sewn up.
二人の関係に綻びが見え始めた。
Cracks began to appear in their relationship.
破れ is a general tear or rip, while 綻び specifically refers to a seam coming apart or a small opening.
裂け目 is a split or fissure, often larger and more violent than the small opening implied by 綻び.
Derived from the verb 綻びる (ほころびる), meaning 'to come apart at the seams' or 'to begin to open'. The noun form refers to the resulting open seam or tear.