I'm sure you looked it up, though in case you didn't, caulk is a thick paste-like substance that drys, usually used to seal gaps between two surfaces, for examp

I'm sure you looked it up, though in case you didn't, caulk is a thick paste-like substance that drys, usually used to seal gaps between two surfaces, for example adding a water proof seal between a shower and the wall, or used around a window pane to eliminate any air gaps. For a person who does home repair, caulk is generally well known. Tip--if you put in a nail or a screw into the tip after you're done caulking, it makes it easier to use the caulk later.