dioptre - glasses, calorie - ?

FOOD
WordClue
HEATwarmth, calorie
CARATglasses - dioptre, diamond - ?
WARMTHheat, calorie
CALORIEglasses - dioptre, food - ?
DIAMONDdioptre - glasses, carat - ?
DIOPTREfood - calorie, glasses - ?
GLASSEScalorie - food, dioptre - ?
GOGGLESsafety glasses
SPECTACLESglasses
CELINEDion, singer
DIAMONDdioptre - glasses, carat - ?