Definition
An archaic Law French adverb meaning "forthwith," "immediately," or "presently." The term appears in early English legal records and pleadings to indicate that an act was to be done or had been done without delay. Some authorities also record a secondary shade of meaning closer to "by and by" or "almost," suggesting the word carried a range of temporal urgency depending on context.
Common Language
No common English counterpart exists. TANTOST is pure Law French legal vocabulary with no surviving ordinary usage.
Why It Matters in Research
TANTOST is a term a researcher is unlikely to encounter outside of medieval and early modern English legal records — year books, plea rolls, and early common law treatises written in Law French. Its practical significance for corpus researchers lies almost entirely in recognition: failure to identify the word as a temporal adverb can distort the meaning of a procedural instruction or a court's directive.
Two points deserve attention. First, the range of meanings recorded — from the urgent "forthwith" to the softer "by and by" — means that context must govern interpretation. A command issued tantost in a proceeding where immediate compliance was expected carries different weight than the same word used loosely to mean "soon." Second, the secondary gloss of "so much" (a meaning closer to the French tant) signals that the term was not always used with strict consistency even in its own era. Researchers reading original Law French texts should be alert to which sense is operative.
Because Law French fell out of active use in English legal practice by the eighteenth century, TANTOST will not appear in modern statutory or case law. It is a reading tool, not a living legal standard.
Historical Dictionary Support
Burrill's Law Dictionary, the sole source here, defines TANTOST as "forthwith; presently; by and by; almost; so much," attributing the entry to Kelham's dictionary of Norman French. The entry is brief and treats the meanings as a cluster rather than distinguishing when each applies, which is characteristic of how Kelham and his successors handled Law French vocabulary — listing attested glosses without resolving the ambiguity among them.
The range Burrill records is itself instructive. "Forthwith" and "presently" suggest immediacy; "by and by" softens that to mean soon but not necessarily instantly; "almost" introduces a further loosening toward approximation; and "so much" is a distinct meaning altogether, tracking the base French word tant. The honest conclusion is that tantost was a term of flexible temporal reference in Law French usage, and no single English equivalent reliably captures it across all contexts.
No broader coverage of this term appears in the standard historical legal dictionaries of the English common law tradition, reflecting the narrowness of its usage to French-language records.