We have gathered 185 distinct terms so far from 20 source documents in 7 disciplines. Many are near-synonyms or otherwise closely related, but we have purposely not merged them in order to maintain all definitional distinctions made by authors. The table below represents one possible classification. Some terms appear in multiple categories, italicized in their secondary location. This grouping builds upon and expands two frameworks discussed in the 2006 NRC report, Learning to Think Spatially: ‘Elements of Spatial Thinking’ and ‘Component Tasks of Spatial Thinking.’ This work in progress is discussed and illustrated further in a recent poster. The concept terms can also be viewed by source, by discipline and alphabetically using the menu options to the left.
Space-time context
Frames of reference
space; space-time; reference frame; place; time; absolute space; field view; object view; frames of reference; place and landscape; space and time; space as time; spatial context; setting; subjective space; virtual reality; positive space; continuity; the void
Primitives of identity
The existence, nature and labeling of things in the world
identity; object; hierarchy; attribute; category; classification; object classification; discrete entities; multiple properties of place; object description; objects and fields; field; part; part-whole; element; group; separation; sign; colour
Spatial relationships
Comparative locations of entities and their parts
direction; location; connection; distribution; adjacency; arrangementorientation; position; transition; proximity; alignment; link; adjacency and connectivity; containment; enclosure; center-periphery; affinitycomplement; congruence; symmetry; local symmetries;  not-separateness; order; ordering; reflection; packing; comparison; contrast; polarity; chirality; shadow
Measurement
of objectsand of relationships and related issues
shape; distance; gradient; magnitude; density; condition; connectivity; length; size; angle; area and volume; dispersion; distance and length; similarity; roughness; spatial sampling; modifiable areal unit; uncertainty
Spatial structures
as observed, and derived from measurement and analysis
boundary; network; pattern; region; neighborhood; path; surface; area; landmark; structure; container; cycle; neighborhood and region; route; center; circuit; branching; web; conduit; coil; alternating repetition; echoes; stratum; object; part; group; event and process
Dynamics
Distinctly spatiotemporal concepts
spatial interaction; diffusion; flow; motion; force; attraction; compulsion; counterforce; blockage; balance; event and process; sequence; duration; frequency; chaosenergetics; navigation; potential; restraint removal; enablement; deformation; folding; interaction; path; cycle
Representation
External tools and mental processses
perspective; map; external representation; map perspective; map projection; representation; mental model; cognitive map; route perspective; survey perspective; point; line; polygon; grid; coordinate; coordinate system; units; object location recall
Transformations
on data
scale; spatial interpolation; interpolation; overlay; spatial integration; buffer; dimensional transformation; map overlay; profile; section; linearizing space; structuring; levels of scale; grain; time cost
Spatial inference
Products of analysis and conclusions drawn
spatial dependence; spatial heterogeneity; distance decay; association; aura; areal association; correlation; spatial model; exceptions; competition for space; access; analog; spatial probability; deep interlock and ambiguity; simplicity and inner calm; density estimation; proximity and distance decay; good shape; strong centers