Statement I put in letters (5)
I believe the answer is:
posit
'statement i put in letters' is the definition.
I can't judge whether this definition defines the answer.
'i put in letters' is the wordplay.
'put in' means one lot of letters goes inside another.
'letters' becomes 'post' (letters in the mail or post).
'i' going inside 'post' is 'POSIT'.
Can you help me to learn more?
(Other definitions for posit that I've seen before include "Assume as a fact or principle" , "Propose" , "Lay down or assume (as the basis for an argument)" , "Put forward as true" , "Put forward; place" .)