The term HILIC stands for
Hydrophilic
Interaction
LIquid
Chromatography.

HILIC is a special case of normal phase chromatography.
Normal phase chromatography is a type of liquid chromatography where the stationary phase is more polar than the mobile phase. The term normal phase used to distinguish this type of chromatography from reverse phase chromatography (this is most common type of analytical separation) where the stationary phase is less polar than the mobile phase. It is used primarily for separation of very polar compounds with a negative log P factor (you can estimate Log P factor of your compounds by going to this web based calculator). See picture below.

 

An application scope of the major types of chromatography techniques for separation of small molecules.