Body of knowledge is the set of topics, their definitions, explanations and other actionable information regarding a specific domain.
Content curation is the gathering, organizing, and online presentation of content related to a particular theme or topic. (source: whatis.techtarget.com/definition/content-curation).
Critical knowledge is unique, highly specialized knowledge that: 1) is essential to your organization’s success; 2) at risk of being lost or compromised; 3) has not been clearly documented; 4) is known by only one or very few individuals (as opposed to common knowledge).
Critical knowledge essentially disappears from your organization every time the person having that knowledge walks out the door at the end of the workday. And it leaves for good when that person decides to transfer or retire. This creates a serious risk.
Similarly, a person without that critical knowledge may need it at some point – perhaps unexpectedly – such as in a crisis situation, or when transitioning into a new position. Rather than have that person acquire the knowledge over a long, painful period of trial and error, it’s better to have a program in place for transferring and growing that knowledge by design, using a repeatable process.
Curation is the organizing and presenting of physical and digital (virtual) objects.
eKnowledge Library is an organized collection of e-bodies of knowledge; the collection as a whole is curated by one or more knowledge librarians; however, each individual e-body of knowledge typically has its own knowledge curator.
Folksonomy is a classification scheme, similar to taxonomy, in which the users themselves define categories informally by tagging content with keywords that they feel are most appropriate.
Information architecture is a discipline and a set of methods that aim to identify and organize information in a purposeful and service-oriented way. 
Knowledge is the capacity to take effective action (the right action, in the right place at the right time) in varied and uncertain situations . The capacity to take effective action also includes observing and deciding which action(s) to take.
Knowledge curation is the capture, classification, organization, transfer, and management of individual, organizational, or community knowledge.
Knowledge Library is a space for facilitating knowledge flows: the creation, organization, curation, sharing, and application of knowledge; it houses one or more bodies of knowledge; the collection as a whole is curated by one or more knowledge librarians; however, each individual body of knowledge typically has its own knowledge curator.
Ontology has many meanings, depending upon the context. In the purest sense, as with most words ending with the suffix ology, it means the study of what is (derived from the Greek root onto, which means “being”).
For the purposes of knowledge curation, we like the following definition: an ontology is a formal, explicit specification of a shared conceptualization. Conceptualization refers to an abstract model of some phenomenon in the world by having identified the relevant concepts of that phenomenon. Explicit means that the type of concepts used, and the constraints on their use are explicitly defined. Formal refers to the fact that the ontology should be machine–readable. Shared reflects the notion that an ontology captures consensual knowledge, that is, it is not private of some individual but accepted by a group. 
Semantic distance refers to the gap which arises when people with different perspectives or viewpoints think and talk differently about the same thing.
Tacit knowledge is knowledge that is so deeply internalized even a seasoned expert has difficulty explaining it to someone or putting it into writing. As opposed to explicit knowledge, such as a set of clearly defined rules (if X happens, then do Y), tacit knowledge is usually governed by deep intuition. You may have heard someone say, “I can’t tell you what it looks like, but I’ll know it when I see it.” That’s usually an indicator of tacit knowledge at work.
Taxonomy is a means of organizing a set of topics or concepts into a hierarchy of categories and subcategories. Well-known taxonomies are The Library of Congress Online Catalog, and the structure used in biology to organize all living things (kingdom, phylum, class, order, family, genus, species).
 M. Cummings in The Encyclopedia of Human-Computer Interaction, Interaction Design Foundation, 2nd Ed.
 A. Bennet & D. Bennet, Organizational Survival in the New World: The Intelligent Complex Adaptive System, Elsevier, 2004.
 R Studer, V R Benjamins, and D Fensel, Knowledge Engineering: Principles and Methods, IEEE Transactions on Data and Knowledge Engineering 25(1-2): p. 185.