In basic terms, "substance" refers to the physical matter of something. It is the stuff that things are made of, like the material an object is composed of. Full definition
Many of us, when we hear the word «addiction,» immediately think of substance abuse in some form. (theravive.com)
If there is a history of substance abuse in your family, tell your child this. (healthychildren.org)
There may be lots of other groups, as well, that have their own reasons for abusing substances in a way similar to that of elite athletes, he says. (sciencenewsforstudents.org)