The online Merriam-Webster gives it two meanings, and dates it from circa 1593
1 : a recalling to mind : reminiscenceSo the second one fits the context of what I read about vets interacting with dog owners.
2 : a preliminary case history of a medical or psychiatric patient
The Encyclopaedia Britannica gives more information about the first aspect of the word:
a recalling to mind, or reminiscence. Anamnesis is often used as a narrative technique in fiction and poetry as well as in memoirs and autobiographies. A notable example is Marcel Proust’s anamnesis brought on by the taste of a madeleine in the first volume of Remembrance of Things Past (1913–27). The word is from the Greek anámnēsis, “to recall or remember.”And then I discovered a page saying it's a concept developed by Plato.
He suggests that the soul is immortal, being repeatedly incarnated; knowledge is actually in the soul from eternity (86b), but each time the soul is incarnated its knowledge is forgotten in the shock of birth. What we think of as learning, then is actually the bringing back of what we'd forgotten. (Once it has been brought back it is true belief, to be turned into genuine knowledge by understanding.) And thus Socrates (and Plato) sees himself, not as a teacher, but as a midwife, aiding with the birth of knowledge that was already there in the student.I guess if I knew this word in a previous life I must have forgotten it.