Mental health (and emotional, generally) terms are inevitably murky. You're not describing a concrete thing. Knowing if what you feel corresponds to what other

Mental health (and emotional, generally) terms are inevitably murky. You're not describing a concrete thing. Knowing if what you feel corresponds to what others feel when they use the same words runs straight into the heart of the "other minds problem." It's a philosophical pickle. Meanwhile, on the academic, clinical or neurological side usage of terms changes over time. They also run into the same problem. There are broad ranges of symptoms to these things, whether they are physical-ish (like mild flue) or mental-ish (like apathy). So, I suggest embracing ambiguity. You just can't one word that describes emotional states or conditions. This is true for a lot of things. Consider "anger." Seems relatively concrete. OTOH, we use it to describe a state of adrenaline fueled rage like you would feel in a fistfight. We use it to describe a long term attitude towards someone. My friend betrayed me 5 years ago. I'm still angry. You're not necessarily feeling the same thing. Add an "-ish" to the end of these concepts. It takes a whole conversation to understand someone's depression (or other states) with any kind of precision. One word only gets you a part of the way.