Thanks to getting cross, one has to pay it (3)
I believe the answer is:
tax
'one has to pay it' is the definition.
I can't tell whether this defines the answer.
'thanks to getting cross' is the wordplay.
'thanks' becomes 'ta' (UK informal version of 'thank you').
'to getting' means one lot of letters go next to another.
'cross' becomes 'x' (an X is a cross).
'ta'+'x'='TAX'
Can you help me to learn more?
(Other definitions for tax that I've seen before include "Are demanding" , "Government levy" , "Overburden with levy?" , "Strain; levy" , "Payment to the Exchequer" .)