IPA: /ˈkrɛs.ləs/
KK: /ˈkrɛs(t)ləs/
Describing something that does not have a crest or decorative top part, often used in relation to coats of arms or similar symbols.
The family was crestless, lacking the traditional emblem that represented their lineage.
Crestless → It is formed from "crest" (from Old French *creste*, meaning the top or peak of something) and "-less" (meaning without). The word "crestless" means without a crest or peak.
Think of something that is 'without' ('-less') a 'top' or 'peak' ('crest') — that's what crestless means.