Definitions:

1. Describes a method where a larger sum of money is paid over time in smaller, scheduled amounts. ADJECTIVE
   • The purchase was made on an installmental basis, allowing her to pay in monthly installments.
2. Refers to something being done, paid, or delivered in installments, that is, in a series of smaller, regular parts rather than all at once. ADJECTIVE
   • The company provided an installmental delivery of the equipment to accomodate the construction timeline.
3. Refers to something that occurs in stages or steps over a period of time. ADJECTIVE
   • The project's installmental completion allowd for thorough quality checks at each stage.

Synonyms:

• incremental
• installment
• installment plan