Definition
Four-fold is an alternative spelling of 'fourfold,' meaning having four parts or aspects, or being multiplied by four. It signifies a quality or quantity increased by a factor of four. Think of it as something increased to four times its original value or something with four distinct elements. The hyphenated form is less common but carries the same meaning as the unhyphenated 'fourfold'. It conveys the sense of an increase to the power of four. The impact is substantial, emphasizing the amplified effect of the fourfold increase.