Old calculator that may make a graduate swear endlessly (6)
I believe the answer is:
abacus
'old calculator' is the definition.
(I've seen this before)
'may make a graduate swear endlessly' is the wordplay.
'may make' becomes 'a' (I can't explain this - if you can you should believe this answer much more).
'a graduate' becomes 'BA' (someone with a Bachelor of Arts degree).
'swear' becomes 'cuss' (synonyms).
'endlessly' means to remove the last letter.
'cuss' with its final letter removed is 'cus'.
'a'+'ba'+'cus'='ABACUS'
'that' acts as a link.
Can you help me to learn more?
(Other definitions for abacus that I've seen before include "An old counting frame with beads" , "Old calculator" , "that one can count on" , "Early counting-frame" , "Basic calculator makes" .)