Prone to mendacity (5)

I believe the answer is:

lying

I believe this is a double definition.

'prone' is the first definition.
(I've seen this before)

'mendacity' is the second definition.
(I've seen this before)

'to' acts as a link.

(Other definitions for lying that I've seen before include "Not standing" , "telling stories" , "Not telling the truth" , "Untruthful - in bed?" , "Prone; fibbing" .)

I've seen this clue in The Globe and Mail.

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