Troth \Troth\, n. [A variant of truth. See Truth.]

1. Belief; faith; fidelity.

Bid her alight And hertroth plight. --Shak.

2. Truth; verity; veracity; as, by my troth. --Shak.

In troth, thou art able to instruct gray hairs. --Addison.

3. Betrothal.

Source: Webster's Revised Unabridged Dictionary (1913)