Articles about Bart’s last letter to Homer (5)
I believe the answer is:
theta
'letter to homer' is the definition.
I can't tell whether this defines the answer.
'articles about bart's last' is the wordplay.
'articles' becomes 'the a' (two grammatical articles).
'about' indicates putting letters inside.
'last' suggests the final letters.
The final letter of 'bart' is 't'.
'thea' enclosing 't' is 'THETA'.
Can you help me to learn more?
(Other definitions for theta that I've seen before include "Eighth letter of Greek alphabet" , "Make amends for" , "Foreign character" , "letter from abroad" , "letter from Argos?" .)