Morpheme
Tro
Type
bound base
Denotation
truth, pledge, oath, promise, loyal, faithful, trustworthy, true
Etymology
Middle English treuthe, trouthe, treowthe, trewthe, treuthen, trouthen, trauthen; Old English trīewþ, trēowþ, trīewþ, trȳwþ, trēowþe, from trēowe, trīewe + -þ
Evidence
betroth, betrothable, betrothal, betrothed, betrothen, betrothing, betrothment, betroths, troth, trothed, trothing, trothless, trothplight, trothplighted, troths
Notes
troth and truth are doublets