The term 'CERTAIN QUALITY' can be described as an AURA, which is a four-letter word. An AURA is an intangible quality or atmosphere that surrounds a person or thing and is often associated with a feeling of mystery or awe. It is often used to describe the presence of a spiritual or supernatural being. In terms of a certain quality, an AURA can be used to describe a feeling of confidence, power, or charisma that someone or something exudes.