I guess I don't really have a definition since I see the term as kinda implying a judgement or something like that. I mean it seems to be used negatively in particular way. I tend to think more in terms of whether or not I'm being demanding and to what degree, is it fair or appropriate, etc. The two could be said to be related I suppose.

I frankly do not like your therapist's definition at all. And it seems to have the potential to inflict both blame and shame, two things that therapists should probably try to avoid since clients usually have enough of that already.

It is obvious to me that there are a ton of things we can't do on our own so I'm not sure where to even begin. All of our relational needs have to involve someone else most of the time and many of our emotional needs do as well. There are others but those are pretty clearly requiring human connection and seem normal and healthy so don't fit under the negative implications of "neediness."