The following is a definition of equanimity, and how equanimity differs from indifference or apathy. The entire quote comes from Shinzen Young:
“Many people get confused about what equanimity is and what it isn’t. Here are some examples that may help clarify.
Equanimity can be deepened by relaxing tension around pain, such as the pain of a broken leg. But equanimity does not mean that you don’t care about getting proper medical attention, such as getting a cast.
Equanimity means opening up to angry sensations that may arise during an argument. But equanimity does not mean that you should stay in a bad relationship.
Equanimity means developing greater acceptance with unpleasant noises in your environment. But it does not mean that you can’t plug your ears or move to another room.
What do all of these examples have in common? You’ll notice that equanimity is a relationship to sensory experience. It’s not a relationship to objective conditions. Letting objective conditions come and go without trying to improve them is indifference. Indifference and equanimity may sound similar, but they’re actually opposites.
Having equanimity with the way a situation makes you feel frees up energy to respond to that situation in an empowered, effective way.”
Source of this description
This description comes from Shinzen Young, in a meditation/mindfulness lesson titled, “Nurturing Self Care”, which is currently free in the Brightmind app. (My understanding is that the Brightmind app will be freely available until March, 2021.)