English Reference
noun

rationale

n.
US /ˌɹæʃəˈnæɫ/ UK /ɹˌæʃənˈæl/ ra·tio·nale UK spelling rationale's, rationale's

  1. 01 C1 Advanced AcademicFormal

    the reasons why someone decides to do something or why something exists.

    the underlying reason or set of reasons that forms the logical basis for an action or belief.

    Simple

    The rationale for the new law was to improve safety on the roads.

    In context

    The CEO provided a detailed rationale for the merger, citing long-term market stability and the potential for technological synergy.

    Usage

    Often followed by the preposition 'for' or 'behind'.

  2. 02 C2 Proficiency ArchaicTechnical Religion

    a special piece of clothing worn by some high-ranking church leaders during ceremonies.

    a liturgical vestment worn by certain Christian bishops, primarily in specific historical or high-church traditions.

    Simple

    The ancient rationale was decorated with gold and precious stones.

    In context

    The museum's collection includes a rare medieval rationale, illustrating the intricate embroidery typical of fourteenth-century liturgical attire.

    Usage

    Used as a countable noun in ecclesiastical contexts.

    vestment

Usage provide rationale

The rationale for moving the voting online is the technical difficulty of requiring fans to vote for multiple acts via text message or phone votes.

BBC News· 14 Aug 2026

You can understand the rationale, which was that female biology should never hold you back.

The Guardian· 12 Aug 2026

Etymology 1

From Late Latin ratiōnāle.

Etymology 2

From Latin ratiōnāle.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level C1 · Advanced
Frequency Frequent
Updated