Software Design/Use a single term to point to a concept

Checklist questions:
 * A single term is used for a concept in variable, function, class names and API documentation?

Why

 * Easiness of change (easier to find all places related to the concept that may need to be changed)
 * Discoverability (easier to find all places related to the concept in the codebase)
 * Apparency of semantics, structuredness, and steepness of learning curve: readers identify the concept quicker