1. In twice the quantity; to twice the degree.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• douyble,
• woobly,
• doulble,
• deebly,
• doully,
• doubley,
• doublin,
• doubek,
• doubkle,
• duble,
• douible,
• doublle,
• dounle,
• dooly,
• dauily,
• adouble,
• doublel,
• donly,
• doeble,
• doubbt

• doily,
• dovel,
• double,
• nobly,
• doubled,
• double-u,
• doubles,
• doubt,
• doable.

The adjective form of the word "doubly" is "double".

The plural form of "doubly" is "doubly". "Doubly" is an adverb and does not change when used in the plural form.

The singular form of the word "doubly" is "double"