'pageant-like' is a modern English compound formed from the noun 'pageant' (a public spectacle or show) and the adjectival suffix '-like' (meaning 'having the quality of').

'pageant' was recorded in Middle English (from around the 14th century) meaning a stage, procession, or spectacle, borrowed from Old French; the suffix '-like' is of Germanic origin and has long been used in English to form adjectives meaning 'resembling'. The combination 'pageant-like' is a straightforward modern compound meaning 'resembling a pageant'.

Originally 'pageant' could refer specifically to medieval staged performances or movable platforms used in processions; over time it broadened to mean any spectacular public display. 'Pageant-like' therefore evolved to describe anything that resembles such a spectacle in showiness or theatricality.