The term 'lacking pigmentation' can be summarized by the word 'albino', which is a 6-letter word. An albino is an organism that has a complete or partial absence of pigment in its skin, hair, and eyes due to a genetic condition. This condition is caused by a lack of melanin, which is the pigment responsible for coloring the skin, hair, and eyes. Albinism is a rare condition that affects people of all races and ethnicities.