Added 10 October 2026 subform noun Categories: Rare Words noun ! Definition from Wiktionary (CC BY-SA). More about subform at Wordnik → Where our words come from → A taxon below the level of form. A secondary window opened from another (parent) window. Origin From sub- + form. From Wiktionary, via Kaikki.org (CC BY-SA) Related Words: subf.formsubsectionvarietysubgenussubphylumsubregnuminfrasectionsuperfamilysectiondivisionphylum Back to today's word