Ancient poet stuck with an unusually old keyboard (8)
I believe the answer is:
virginal
'ancient poet stuck' is the definition.
I can't tell whether this defines the answer.
'with an unusually old keyboard' is the wordplay.
'with' means one lot of letters goes inside another.
'unusually' indicates anagramming the letters.
'old keyboard' becomes 'virgil' (I can't justify this - if you can you should believe this answer much more).
'an' anagrammed gives 'na'.
'na' inserted within 'virgil' is 'VIRGINAL'.
Can you help me to learn more?
(Other definitions for virginal that I've seen before include "Pure - very early keyboard instrument" , "Untouched - smaller version of the harpsichord" , "Untouched - old keyboard instrument" , "Rectangular harpsichord" , "Untouched - spinet" .)