'iconless' originates from Modern English, specifically built from the noun 'icon' plus the suffix '-less', where 'icon' comes from Greek 'eikōn' meaning 'image' and the suffix '-less' comes from Old English 'lēas' meaning 'free from, without'.

'icon' changed from Greek 'eikōn' into Late Latin 'iconon', then into Old French 'icone' and Middle English 'icone' before becoming the modern English 'icon'. The suffix '-less' developed from Old English 'lēas' into Middle English '-les' and combined with nouns to form adjectives meaning 'without'. These elements combined in Modern English to form 'iconless'.

Initially the parts meant 'image' (for 'icon') and 'without' (for '-less'), so the compound originally conveyed 'without an image'; over time it has come to be used specifically for interfaces (i.e., 'without icons') and more broadly for 'lacking symbolic/iconic representation'.