A synonym for “dismember” could be “dissect”.
“Dissect” implies a careful and detailed cutting apart or analysis. For example, “The scientist dissected the specimen to understand its internal structure.” While it is often used in a scientific context, it can also convey the sense of breaking something down into its constituent parts, similar to “dismember”.
Another option is “fragment”. “Fragment” can mean to break or split into pieces. For instance, “The explosion fragmented the object into countless pieces.” This word emphasizes the result of being broken up into smaller parts, which is similar to what happens when something is dismembered.
“tear apart” is also a possible synonym. It has a more forceful and violent connotation. For example, “The wild animal tore apart its prey.” This phrase suggests a violent act of separation, which is in line with the idea of dismembering.