Decimal base equal to being rationally defensible (7)
I believe the answer is:
tenable
'rationally defensible' is the definition.
'tenable' can be an answer for 'defensible' (I've seen this in another clue). I'm not certain of the 'rationally' bit.
'decimal base equal to' is the wordplay.
'decimal base' becomes 'ten' (I've seen this before).
'equal to' becomes 'able' (I've seen this in another clue).
'ten'+'able'='TENABLE'
'being' is the link.
Can you help me to learn more?
(Other definitions for tenable that I've seen before include "Believable" , "possible to maintain" , "Able to be held" , "Well-founded" , "Of argument, rational and defensible" .)