Entry 2 senses Webster, 1913 caulking · caulk·ing · IPA /kˈɔkɪŋ/ 01 n. the process of sealing cracks and crevices with a filler such as caulk{2}. 1. the process of sealing cracks and crevices with a filler such as caulk{2}. 2. same as caulk{2}, n.. See: caulk{2}