Definition
A Latin and Law Latin term meaning "rate" or "proportion." Used in old English legal sources to express a fixed or established measure of apportionment — the share or fractional part to which a party is entitled or liable. The term appears almost exclusively as a component of longer Latin phrases in legal instruments and court records, most commonly *pro rata* (in proportion) and *juxta ratam* (according to the rate or proportion aforesaid). Standing alone, *rata* simply supplies the root concept: a calculated, proportionate share rather than an arbitrary or fixed amount.
Common Language
Modern common usage (Wiktionary): Any of various New Zealand plants of the genus *Metrosideros*; also, the hard dark red wood produced by those trees.
Historical common usage (Webster's 1913): A New Zealand forest tree (*Metrosideros robusta*), and its hard dark red wood, used by the Maoris for paddles and war clubs.
The legal term *rata* has no connection whatsoever to the botanical common word. Researchers encountering *rata* in legal Latin contexts should not expect any ordinary English dictionary to be useful; the term belongs entirely to the Law Latin vocabulary inherited from Roman and medieval legal practice.
Common Confusion
*Rata* is frequently encountered only as a fragment of a longer phrase — most often *pro rata* — and researchers may not recognize it as a discrete legal term with independent meaning. The confusion runs in both directions: some sources treat *pro rata* as a single indivisible unit without explaining that *rata* alone carries the core sense of "rate" or "proportion," while others (including Burrill) define *rata* separately but rely on the reader to connect it to *pro rata* usage. Additionally, *rata* should not be conflated with *ratum* (a thing ratified or confirmed), which shares a Latin root but carries an entirely different legal sense related to ratification and validity.
Why It Matters in Research
*Rata* surfaces in old English law reports and pleading records primarily as a term of art in Latin formulae. Researchers working in the Law Mind corpus on pre-eighteenth-century English materials — particularly records involving apportionment of rents, taxes, debts, or shares among multiple parties — will encounter *rata* and *juxta ratam* in contexts where modern editors may leave the Latin untranslated. Burrill's single citation to Dyer's Reports (82, French edition) and to 4 Modern 79 signals that the term's substantive legal work was largely done by the surrounding phrase, not by *rata* alone.
The critical navigational point: searching for *rata* in historical corpus sources will surface far more results for *pro rata* than for *rata* standing alone. Researchers should treat *rata* as an index term pointing to the broader cluster of proportionality doctrine — apportionment, contribution, and ratable distribution — rather than as a term with an extensive standalone doctrinal history.
For post-eighteenth-century materials, *rata* as an isolated term nearly disappears; English legal writing replaced Latin formulae with vernacular equivalents ("ratably," "in proportion," "pro rata share"), though *pro rata* itself persisted as a term of art into modern usage.
Historical Dictionary Support
Burrill's Law Dictionary provides the only substantive entry among the shelf sources. Burrill defines *rata* concisely as "a rate; a proportion" within old English law, and supports the definition with two citations: *4 Mod. 79* and Dyer's Reports at page 82 (French edition). The brevity of the entry reflects the term's status: *rata* was a functional building block of legal Latin phrasing, not a concept that generated its own doctrinal apparatus. Burrill's inclusion of *juxta ratam præd'* (according to the rate aforesaid) is instructive — it shows how the term operated in practice as a cross-reference device within instruments, pointing back to a previously stated proportional calculation.
No other historical dictionary in the Law Mind shelf independently defines *rata* as a standalone entry; the concept is typically absorbed into entries for *pro rata* or related terms. This gap is itself informative: it confirms that *rata* was understood as a derivative or abbreviation, not an originating legal concept.
Encyclopedia Cross-Reference
See: PRO RATA