An interpretation is an engagement with something in which an agent is committed to working out, developing, and refining one of the possible ways of making sense of it. Interpretation involves addressing something as something, or putting it to use as something. In an interpretive commitment to a possibility, an agent develops a prior understanding by applying it in a specific situation.

Heidegger defines guilt in general as a condition in which an agent is the reason for a lack, and there is no adequate reason (as judged according to our shared standards for judging such things) that could justify being the reason for the lack. Existential guilt is a species of this more general form of guilt, and consists in being the null reason for a nullity – that is, the agent in question is responsible without adequate justification (i.e., the agent is a null reason) for a form of existence that negates or extinguishes other possible forms of existence (a nullity).

“Unconcealment” is heidegger’s preferred (and rather literal) rendering of the Greek ἀλήθεια (), which is usually translated as “truth.” Heidegger maintains that both our ordinary notion of truth as rightness or correctness (Richtigkeit) and the traditional conception of truth as agreement or correspondence (Übereinstimmung) presuppose what he believes the Archaic Greek poets and pre-Socratic thinkers understood by ἀλήθεια, namely, the uncovering of entities, the disclosedness of Dasein, and the unconcealment of being (Sein).

A reference is an essential structural feature of worldly entities, namely, the way such entities always send or direct their user to something else. The German word for “reference” – Verweisung – Verweisung – is also sometimes translated “assignment.” The verb verweisen means to refer in the sense of literally sending one person to another person, in the way that a doctor refers a patient to a specialist. References are constitutive of equipment, because “strictly speaking, there ‘is’ never just one equipment. To the being of equipment a whole of equipment always belongs.

Fittingness (fug) is a condition in which entities are adapted or suited to the situation in which they belong, and thus are in a suitable state for interacting with each other. Heidegger argues that entities are disclosed in their being when we grasp their fittingness (i.e., the conditions under which they are connected, adapted, and adjusted to each other), and thus fittingness is an ontological concept.

An affordance is the opportunity to act that an environment offers an agent. Affordances are a function of, on the one hand, the projects, abilities, skills, and dispositions of the specific agent and, on the other hand, the possibilities furnished by the equipment the agent encounters when that equipment is situated in a whole context of equipment.

An abyss in general is something that cannot be fathomed – that is, a phenomenon that defeats any effort to explain, determine, define, rationalize it, or make it intelligible using conceptual resources. Heidegger also uses “abyss” as a term of art to refer to a specific and important type of abyss in the more general sense. “Abyss” in Heidegger’s specific sense is something that grounds the being of a thing precisely by refusing to determine it.

A disposition in general is either the process by means of which a struggle, conflict, or dispute reaches a resolution; or it is the condition in which a formerly fluid, dynamic, changing situation is now settled into a more static, orderly arrangement and thus brought to a kind of completion. Heidegger is interested in ontological dispositions: the settlement of stable configurations of relations that allows entities to manifest themselves. Heidegger’s metaphor for understanding the concept of a disposition is a threshold – the hardened boundary that delimits the inside from the outside and vice versa (see GA12:24/PLT 202). Without a threshold to secure and carry a doorway or gate, the distinction between in and out is insecure and vague. With a threshold in place, the relation of in and out is made stable or brought to a resolution.