IPA: /ˌhaɪəroʊˈɡlɪfɪkəl/
KK: /haɪəroʊˈɡlɪfɪkəl/
Relating to or resembling the characters used in ancient Egyptian writing, which are symbols that represent sounds or ideas.
The archaeologist studied the hieroglyphical inscriptions on the ancient temple walls.
Hieroglyphical → It is formed from "hieroglyph" (from Greek "hieroglyphikos", meaning sacred carving) and the suffix "-ical" (meaning pertaining to). The word "hieroglyphical" refers to something that pertains to sacred carvings, particularly the writing system used in ancient Egypt.
Think of 'sacred carving' ('hieroglyph') to remember that 'hieroglyphical' relates to the writing system of ancient Egypt.