Definition
Pecunia trajectitia (Latin: "money carried across the sea") is a term from Roman civil law describing a loan of money — or of goods purchased with borrowed money — extended specifically for a maritime voyage, in which the lender assumes the risk of loss from the vessel's departure until its arrival at the destination port. Because the lender bears the peril of the sea, the loan is discharged if the vessel is lost; in exchange, when interest is stipulated, it may be charged at a rate exceeding ordinary legal limits. That stipulated maritime interest is separately termed nauticum foenus (or faenus nauticum).
The concept is the Roman law ancestor of what later maritime practice would call bottomry and respondentia. Bottomry involves a loan secured on the ship itself; respondentia involves a loan secured on the cargo. Pecunia trajectitia is the broader Roman category encompassing either arrangement, defined less by the security given than by the allocation of sea risk to the lender.
Common Confusion
PECUNIA TRAJECTITIA / FAENUS NAUTICUM / BOTTOMRY / RESPONDENTIA: These four terms circulate in maritime legal sources and are frequently treated as interchangeable. They are not. Pecunia trajectitia names the underlying Roman law loan transaction — money lent at sea risk. Faenus nauticum names the interest charged on that loan when the parties stipulate for it. Bottomry and respondentia are the later common law and admiralty instruments that evolved from the Roman model: bottomry pledges the ship as security; respondentia pledges the cargo. A researcher encountering pecunia trajectitia in a civil law digest or admiralty treatise should not assume it maps cleanly onto either bottomry or respondentia without reading the specific context.
Why It Matters in Research
Pecunia trajectitia appears almost exclusively in one context: historical admiralty and maritime law scholarship, particularly sources engaging Roman civil law foundations of the law of the sea. Researchers encountering this term are most likely working in one of three places — a translation or digest of the Corpus Juris Civilis (especially Digest 22.2), an early modern maritime treatise such as Molloy's De Jure Maritimo, or an American admiralty decision from the early nineteenth century in which federal judges were actively reconciling civil law doctrine with common law admiralty practice.
The term essentially disappears from American and English practice after the mid-nineteenth century, replaced entirely by bottomry and respondentia as operative legal categories. Finding pecunia trajectitia in a case reporter after roughly 1860 is unusual and likely signals either a scholarly appendix, a historical digest, or a court specifically tracing doctrinal origins.
One navigational trap: some historical sources use pecunia trajectitia as a synonym for faenus nauticum rather than distinguishing the loan from the interest. Black's entry, for instance, slides between the two by noting that interest "does not necessarily arise from this loan, but when it is stipulated for it is termed nauticum foenus" — making clear the concepts are related but distinct. Burrill is more precise, calling it "another name for faenus nauticum" while also quoting Molloy's definition emphasizing the sea-hazard element. This inconsistency in the source dictionaries mirrors genuine inconsistency in the historical literature, and researchers should check which sense a given author intends.
Story's treatment in the admiralty reports (cited by Burrill at 2 Sumner's Reports 157, 181) is the most important American judicial engagement with this doctrine and offers the most analytically rigorous discussion of the Roman foundations in an English-language judicial source.
Historical Dictionary Support
The three shelf dictionaries converge on the core: pecunia trajectitia is a Roman civil law maritime loan in which the lender assumes sea risk. Their divergences are instructive.
Rapalje & Lawrence offer the most literal rendering — "money carried across the sea (que trans mare vehitur)" — and treat the term primarily as a translation aid, pointing the researcher toward the Roman source concept without extended analysis.
Black's provides the most practically oriented definition, emphasizing the contract structure: the debtor purchases goods with borrowed money, ships them, and the creditor bears the loss risk for the voyage period. Black's is also the only shelf source that explicitly defines the interest dimension as a separate term (nauticum foenus), which helpfully flags the conceptual split for the researcher.
Burrill is the most scholarly, citing Digest 22.2.1 directly and Molloy's De Jure Maritimo alongside the Story reference. Burrill's entry treats the term as essentially equivalent to faenus nauticum while acknowledging the literal meaning emphasizes the loan itself. This is the entry most useful for a researcher trying to trace Roman origins forward into admiralty practice.
What all three sources omit: any discussion of how pecunia trajectitia doctrine influenced the development of insurance law. The allocation of risk to the lender in exchange for premium-rate interest is structurally parallel to early marine insurance, and some legal historians have argued the two developed in tandem. Researchers working at the intersection of maritime lending and insurance history will need to go beyond these dictionary entries.
Jurisdictional Note
Pecunia trajectitia is a Roman civil law category, not a common law one. In American admiralty courts, which drew on both civil and common law traditions, the concept informed early bottomry and respondentia doctrine but was not directly applied as a cause of action. Civil law jurisdictions with Roman law heritage (notably Louisiana and certain European systems) maintained closer terminological continuity with the Roman category.