rationale

rationale — noun

1. a set of logical reasons that explain why a particular decision was made, a plan

1.nounB2
Definition

a set of logical reasons that explain why a particular decision was made, a plan was chosen, or a belief is held

Example

The store manager explained the rationale behind the new opening hours to her team.

rationale + behind + noun

When Hassan asked about the budget cuts, the director laid out his full rationale.

lay out + rationale (collocation)

Common collocations
  • rationale for
  • rationale behind
  • main rationale
  • underlying rationale
  • explain the rationale
  • understand the rationale
  • provide a rationale
  • set out the rationale
Synonyms
  • reasoning

    focuses on the thought process or chain of logic, while rationale refers to the full set of reasons

  • logic

    emphasises the systematic, coherent structure of the argument rather than the reasons themselves

  • basis

    suggests the fundamental starting point or foundation, often less detailed than a full rationale

  • justification

    carries a stronger sense of defending or proving something is right

Grammar Patterns

rationale + for + noun/-ing

rationale + behind + noun

Usage Note

More formal than reason. Typically used in academic, legal, or business writing. The word often refers to a complete or organized set of reasons rather than a single simple explanation. Commonly paired with the prepositions for or behind.

Common Mistakes

What was your rationale for being late?
What was your reason for being late?
rationale sounds overly formal for everyday situations like lateness; use reason instead.

Word family

  • rational
    adjectiveB2
  • rationally
    adverbB2
  • rationality
    nounC1
  • rationalize
    verbC1
  • rationalization
    nounC1
  • irrational
    adjectiveB2
  • irrationality
    nounC1

Synonym discussion

Sense: noun/1

All four words relate to the reasons behind something, but they differ in emphasis. Reasoning focuses on the mental process of connecting ideas — how you get from facts to a conclusion. Logic stresses the structural soundness of the argument, whether the steps follow from one another correctly. Basis points to the fundamental foundation on which a decision or belief rests, often just one key factor rather than a full explanation. Justification carries a defensive tone: you are proving that your action was right or reasonable, especially when it has been questioned. For example, you might explain the reasoning behind a maths problem, check the logic of a legal argument, give the basis for your trust in someone, and offer a justification for raising prices.

reasoning ↗logic ↗basis ↗justification ↗

Common collocations

Nouns

Prepositions

Etymology

LatinFrenchEnglish

The word rationale comes from the Latin rationalis, meaning 'of or belonging to reason', which itself comes from ratio ('reason, calculation, account'). It entered English in the mid-1600s via French, first used in philosophy and theology to mean a reasoned explanation of principles or beliefs. By the 1800s it had spread into general academic and professional writing.