序

Core senses center on the arrangement of one thing after another: sequential or temporal progression; hierarchical or social rank and ritual precedence; spatial arrangements (such as rows). In literary contexts, it typically denotes a preface or introductory section.

Functions as a noun (a sequence, rank, or preface), a verb (to arrange in order, to introduce/preface a text), or a modifier/adverbial (in sequence, orderly).

Distinguish between the act of ordering (process) and the resulting state of being ordered. Differentiate between "series" (a collection of similar items) and "sequence" (a specific trajectory from point A to B). Note a semantic overlap with 徐 (slow/gradual), where 序 can imply a measured, gradual progression.

If a translation of "sequence" feels too static or mechanical in context, test the sense of a "measured pace."