What speakers mean by it now
In present-day English, truth is first of all correspondence with fact: the way things are, a report that matches them, or a proposition held to be so. People tell the truth, hunt for the truth, and argue over scientific or moral truths. A narrower workshop sense still exists, especially in British technical English: the truth of a plane, a plough, or a measurement is how closely it sits to a standard. Older layers have not been wiped out. The word can still mean sincerity in speech and action, or loyalty to a person, a feeling, or an original. Those uses sit closer to the earliest English sense than the courtroom demand for an accurate account of events.
Inherited, not imported
The origin of the word truth is Germanic inheritance, not a loan from Latin veritas or Old French verité. Those Romance forms arrived later and now live beside it as learned or borrowed companions. English already named the idea in the Old English period. West Saxon had triewð; Mercian had treowð. Both named faith, faithfulness, loyalty to kin, friends, or country, the habit of keeping faith, veracity, and also a pledge or covenant. First-use notes in standard dictionaries place the noun before the twelfth century, which is another way of saying it is attested in Old English itself.
Middle English kept the inheritance under a cloud of spellings: treuth, trouthe, trewthe, truþ, and others. Modern truth is the survivor of that cluster. Nothing in that path looks like a one-time borrowing. Speakers did not fetch a foreign label for a concept they lacked. They carried forward the abstract noun that belonged with the adjective now spelled true.
True plus an old ending
On the surface the morphology is honest. Truth is true with the native abstract suffix -th, the same ending that yields warmth, strength, and width. That analysis matches the historical derivation; it is not a later folk story. Comparative reconstruction sets a Proto-Germanic feminine triwwiþō, built from triwwiz (faithful, marked by good faith) and the abstract suffix -iþō. Old English trēowþ is the West Germanic continuation of that noun.
Cognates keep the older social sense more clearly than modern English does. Icelandic tryggð still means loyalty or fidelity. Norwegian trygd has meant trustworthiness and, in later use, a form of social security. The related adjective is widespread: Old Norse tryggr, Gothic triggws, Dutch getrouw, German treu. English trust and truce sit in the same neighborhood, as does troth, a doublet of truth rather than a separate root.
A deeper Indo-European step is offered in many handbooks, following Watkins, as a suffixed form of a root deru- (also cited as drew-o- or drewH-) with a basic sense of being firm, solid, or steadfast. The same root is proposed for English tree and for words meaning oak, timber, or strength in several related languages. That link is a reconstruction from comparison, not a medieval explanation that Old English speakers would have recited. If it is right, firm wood and firm loyalty share an image of standing fast. If it is wrong, the Germanic story still holds on its own: an adjective of good faith, plus a suffix that turns adjectives into qualities.
From a bond to a statement
The shape of the word barely changed. The job of the word did. In early English the noun clustered around interpersonal reliability: keeping faith, standing by a contract, remaining loyal in marriage or in war. Medieval texts use it of military covenants and marriage bonds. Glosses sometimes pair it with Latin terms for a pact or a treaty. The later, now dominant sense — something that is true, a true statement or proposition — is recorded by the middle of the fourteenth century. By the late fourteenth century the word could also name what is righteous, aligned with a divine standard, or sound religious teaching. A more explicit philosophical gloss, accuracy or correctness as conformity of thought with fact, is dated to the 1560s. An interjection of assent, used like a stamp of emphasis, appears in the sixteenth century.
The older meaning did not vanish so much as split. Troth, a phonetic variant of the same Old English noun, kept the pledge sense in northern and Midland dialect and in set phrases about plighting a bond. Standard truth moved toward correspondence with the world, while still allowing talk of being true to someone. Legal English holds both layers at once. An oath to tell the truth is a promise of fidelity that is supposed to produce an accurate report. Late medieval legal records already speak of jurors seeking a plain or naked account of circumstance, which suggests that the measure of the word was shifting from inner intention toward an external state of affairs. That is a historian’s reading of the documents, not a single dictionary line, but it lines up with the dates given independently by etymological sources.
English also never grew a basic verb meaning speak the truth as a counterpart to lie. Speakers use phrases: tell the truth, speak truly, be honest. The gap is a reminder that the noun grew from an adjective of steadfastness, not from a speech-act verb.
The twin that kept the old job
The most concrete leftover of the older noun is troth. Same ancestor, same suffix, a later pronunciation that went its own way. Where truth now answers a question about fact, troth still answers a question about a bond. Anyone who hears both can still hear the original work of the word: not to name a proposition first, but to name the firmness that made a promise hold.