When you are being glacial, and icy to people on purpose, to make yourself appear intelligent and aloof.
Usually used to make yourself appear attractive to a member of the opposite sex who is chasing you.
Like playing hard-to-get!
Gina was full of glaciosity at Andy's parteh. She wanted to make Andy chase after her. She ignored him for the whole night!!
an adjective that describes the present state that either a person or an object is in whereby it appears to have or give off a glow that is radiating outward as if it is being lit from within.