Definition of transparencies:
(n) :
(uncountable) Openness; accessibility to scrutiny.
(n) :
(uncountable) The quality of being transparent.
(n) :
(countable) Something transparent.
(n) :
(countable, photography) A translucent film-like material with an image imprinted on it, viewable by shining light through it.
(n) :
(countable, art) A transparent artwork, viewable by shining light through it.
(n) :
(signal processing) Sufficient accuracy to make the compressed result perceptually indistinguishable from the uncompressed input.