Definitions Of Vitiligo :

1: An acquired absence of pigment found in spots or patches , although the margin of these spots shows an increased amount of pigment matter
(J.Henery Allen)

2: Loss of pigmentation characterized by various shaped and sized , smooth non elevated , non-infiltrated usually sharply demarcated patches at times with slightly hyperpigmented borders.(Sulzberger Woy Witten) 

3: An acquried disease characterized by the progressive disappearance of normal pigmentation in variously shaped and sized white , smooth sharply defined patches with hyperpigmented borders (F M Dearborn)

4: Vitiligo or leucoderma is an affection characterized by circumscribed patches of skin , from which the pigment has disappeared to a lesser or greater extent  ( Douglass )

5: Vitiligo is an acquired idiopathic depigmentary condition charterised by completely depigmented patches of various sizes and shapes. (P.N Behl)

6: Patches of skin loosing their pigment and becoming perfectly white without any other changes taking place in them and particularly without any scaling. ( Rochburgh )

7: Asymptomatic depigmented macules of various shapes and sizes with the rest of skin otherwise remaining normal. (J.S Pasricha)

8: Vitiligo is a very common , acquired , patchy macular , chronic depigmenting disorders which affects at least 1% of the population and is usually progressive over many years. ( Moschella and Hurley )

9: Vitiligo is a condition of unknown etiology characterized by depigmented patches in the skin which retain its normal texture.( Sneddon,l B )
 
10: Vitiligo is a common acquired idiopathic hypomelanosis which is often familial and which is characterized by pale white macules that enlarge centrifugally over time. ( Thomas B Fitzapatric )

11: Vitiligo ( Vit-ill-eye-go ) is a pigmentation disorder in which white patches appear on the skin on different parts of the body and the affected area may trun white.
( National Institute Of Arthritis And Muskuloskeletal And Skin Disease )