OK, those are three quite different things.
Modelica allows you to create models in a similar way to spice by describing components and how they are connected. But instead of a netlist of nodes, Modelica has a concept of connectors. But otherwise it is fairly similar. However, Modelica's scope is well beyond that of Spice or Verilog-A. Those languages claim that by analogy they can do other domains but you are mainly limited to simple "equivalent" circuit models for thermal systems and their analogies to mechanical systems are (in my opinion), hopelessly flawed. Not to mention that there are high quality libraries in Modelica for modeling multibody systems and two phase fluid systems...things I would never attempt in Spice or Verilog-A.
As for Simulink...that is an entirely different beast. Simulink's focus is on modeling of dynamics using a representation of the _math_, not the physics. What this means in practice is that when you build a model you translate the text book equations into a _causalized_ mathematical representation of your system. The problem with this is that changing even very basic assumptions will require you to re-causalize the system of equations and this is quite tedious, time-consuming and error prone. The way I always describe it is that Simulink is like performing long division (you do all the tedious, time consuming and error prone work yourself) whereas Modelica is like a calculator (it does all that stuff for you and just helps you get to the answer quickly). But the key point about Modelica is that it leverages a compiler that does a ton of work for you (not just causlization but state selection, index reduction, etc). Now MathWorks has Simscape that supports this "acausal" approach that Modelica uses, but in my opinion Modelica is not only technically better and more powerful, but also more open (see OpenModelica, for example).