'uniformly-awned' originates from Modern English, specifically the elements 'uniformly' and 'awned', where 'uniformly' derives from the adjective 'uniform' (ultimately from Latin 'uniformis', with 'uni-' meaning 'one' and 'form' meaning 'shape') and 'awned' is formed from 'awn' (a Germanic-origin word meaning 'bristle') plus the suffix '-ed' meaning 'having'.

'uniform' passed from Latin 'uniformis' into Old French and Middle English as 'uniform', becoming the Modern English 'uniform'; 'awn' evolved through Old and Middle English forms (recorded in Middle English as 'aune'/'awne') into modern 'awn'; the compound 'uniformly-awned' is a Modern English descriptive formation combining these elements.

Initially the separate parts referred to 'one shape' ('uniform') and 'a bristle' ('awn'); over time, combining them in Modern English produced the descriptive compound meaning 'having bristles distributed evenly' as used in botanical contexts.