Kind of frozen liquid, less cold, put into glasses (7)
I believe the answer is:
species
'kind' is the definition.
(species is a kind of kind)
'frozen liquid less cold put into glasses' is the wordplay.
'frozen liquid' becomes 'ice' (frozen water).
'less' indicates named letters should be taken away (less can mean minus).
'cold' becomes 'C' (eg on taps).
'put into' indicates putting letters inside.
'glasses' becomes 'specs' (spectacles).
'ice' with 'c' taken away is 'ie'.
'ie' going inside 'specs' is 'SPECIES'.
'of' acts as a link.
(Other definitions for species that I've seen before include "Category" , "Kind, sort" , "Kind of creature" , "Living group; kind" , "Variety, taxonomic group" .)