We don't have synonyms for voxel yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are vowel, vogel and vovel.
(n) :
(computer graphics) The three-dimensional analogue of a pixel; a volume element representing some numerical quantity, such as the colour, of a point in three-dimensional space, used in the visualisation and analysis of three-dimensional (especially scientific and medical) data.
(n) :
(computer graphics) The three-dimensional analogue of a pixel; a volume element representing some numerical quantity, such as the colour, of a point in three-dimensional space, used in the visualisation and analysis of three-dimensional (especially scientific and medical) data.