"Is that so?” (6)
'is that so?' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for really that I've seen before include "without a doubt" , "surely not?" , "Go on" , "In truth - one may be surprised to say it" , "In genuine way" .)
'is that so?' is the definition.
(I've seen this in another clue)
This is all the clue.
'is that so?' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Another definition for oh yeah that I've seen is " Exclamation of disbelief".)