Oddly cheap current furniture keeps being satisfactory (10)
I believe the answer is:
acceptable
'being satisfactory' is the definition.
(synonyms)
'oddly cheap current furniture keeps' is the wordplay.
'oddly' indicates alternate letters (letters in the odd-numbered positions are used).
'current' becomes 'ac' (alternating current).
'furniture' becomes 'table' (table is a kind of furniture).
'keeps' is an insertion indicator (inserted letters are kept inside).
The alternate letters of 'cheap' are 'cep'.
'ac'+'table'='actable'
'cep' inserted within 'actable' is 'ACCEPTABLE'.
(Other definitions for acceptable that I've seen before include "Of (marginally) satisfactory quality" , "Satisfactory, adequate" .)