IPA: //haɪpəˈstoʊm//
KK: /haɪpəˌstoʊm/
A part located near the mouth of certain insects and arachnids, often serving as an appendage or structure related to feeding.
The hypostome helps the tick attach to its host while feeding.
Hypostome is formed from "hypo-" (meaning under) and "stoma" (from Greek "στόμα", meaning mouth). The word refers to a structure that is located beneath the mouth or a mouth-like opening.
Think of something that is 'under' ('hypo-') a 'mouth' ('stoma') — that's why hypostome refers to a structure located beneath a mouth.