Here’s a free definition for your buzzword bingo card…
Conspectus: an approach to defining the levels at which an institution collects in a given content area. It’s about the depth of collecting and there are standard indicators, which you can read about in this IFLA guide to collection development policies. Conspectus is also an approach that can be taken to collection development policy writing, where the policy sets out the target level of depth in particular areas of collecting. It’s not used much in Australian libraries any more, and is a bit out of fashion internationally (though used by some research libraries still).