Fancy one short speech is using computer technology? (7)
I believe the answer is:
digital
'using computer technology?' is the definition.
'fancy one short speech' is the wordplay.
'fancy' becomes 'dig'.
'one' becomes 'i' (Roman numeral).
'short' means to remove the last letter.
'speech' becomes 'talk' (talk is a kind of speech).
'talk' with its last letter taken away is 'tal'.
'dig'+'i'+'tal'='DIGITAL'
'is' acts as a link.
(Other definitions for digital that I've seen before include "Replacement for analogue" , "computerised?" , "Using fingers" , "Works with through numerals, like watch" , "Sort of radio" .)