The word "dispensable" is an adjective that describes something that is not necessary or essential. In other words, if something is dispensable, it can be removed or done without without causing any problems.
In more formal or academic writing, "dispensable" can refer to elements in theories or systems that are not crucial for the main concept to work. For instance, "In this model, some variables are dispensable and do not significantly affect the outcome."
While "dispensable" primarily means something that can be done without, it can also refer to things that are not required by law or regulation.
Currently, "dispensable" does not have specific idioms or phrasal verbs directly associated with it. However, you might encounter phrases like: - "Can be done without" (similar meaning) - "Not a deal-breaker" (indicating something that is dispensable)
To sum up, "dispensable" means something that you can do without.