膨大

1. Origins, structure, and basic meaning

• Structure: 膨大, read ぼうだい, is a な-adjective for an extremely large volume of material or demand on time and effort.
• Basic usage: It takes な before nouns of scale or resources, as in 膨大な量 and 膨大な時間と労力.

2. Common pitfalls and similar expressions

• Volume and resource demand
  • It can describe not only a mass of records but also the enormous time and effort required for a task.
• Amount versus physical size
  • The word is especially suited to vast accumulated quantity or scope, rather than simply the external size of one object.