1 definition by Andreas Anstruther-Gough-Calthorpe of Roxburgh

adj - not up to expectations; "a disappointing performance from one who had seemed so promising" Generally used by posh blokes with long hair and rippled six-packs. Occasionally prefixed by the word 'extremely' to express a greater level of concern over his hopes, desires, intentions or expectations being dashed.
His retiring foe Shrinks from the wound, and disappoints the blow - Addison

That treble 20 has to go down as extremely disappointing - Cox
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