五つ

1. Origins, structure, and basic meaning

• Structure: 五つ (いつつ) combines numeral 五 with native counting form つ to count five general items.
• Basic usage: 五つ is the native Japanese quantity expression for five general items.

2. Common pitfalls and similar expressions

• Native quantity and calendar date
  • The calendar date written 五日 is read いつか, so its reading and use are different.