Realistic, i.e. not up in the air (4-2-5)
I believe the answer is:
down-to-earth
'realistic' is the definition.
(I've seen this before)
'i e not up in the air' is the wordplay.
I cannot really understand how this works, but
'i' could be 'a' and 'a' is found within the answer.
'e' is within the answer.
an anagram of 'not' is 'nto' which is located in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for down-to-earth that I've seen before include "where Newton's apple fell?" , "Far from assuming" , "Sensible - practical - realistic" , "Practical, no-nonsense" .)