A more thorough explanation:

Definition: Indecimable (in-des-uh-muh-buhl), adj. Hist. Not titheable; not liable for tithes.

Example: In medieval times, certain lands were considered indecimable, meaning they were exempt from paying tithes to the church.

Explanation: Tithes were a tax paid to the church, usually in the form of one-tenth of a person's income or produce. However, some lands were exempt from this tax, and were therefore considered indecimable. This term is no longer commonly used, but it provides insight into the historical relationship between the church and the people it served.