waistlinePronunciation: /ˈweɪs(t)lʌɪn/Translate waistline | into French | into German | into Italian | into Spanish Definition of waistline noun 1the measurement around a person’s body at the waist:eliminating inches from the waistline the shaping and position of the waist of a garment: the changing waistline in women’s fashions 2an imaginary line around a car or other vehicle at the level of the bottom of the windows. waistline in other Oxford dictionaries Definition of waistline in the US English dictionary