Cross out times table, finally (5)
I believe the answer is:
erase
'cross out' is the definition.
'times table finally' is the wordplay.
'times' becomes 'eras' (era is a kind of time).
'finally' says to take the final letters.
The last letter of 'table' is 'e'.
'eras'+'e'='ERASE'
(Other definitions for erase that I've seen before include "score" , "Eliminate" , "Remove from memory" , "Remove recorded material" , "Destroy recording on audio or video tape" .)