Has to modify strong language (5)

I believe the answer is:

oaths

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'has to modify strong language' is the definition.
I can't judge whether this defines the answer.

'has to modify' is the wordplay.
'modify' indicates anagramming the letters (I've seen 'modified' mean this).
'has'+'to'='hasto'
'hasto' with letters rearranged gives 'OATHS'.

Can you help me to learn more?

(Other definitions for oaths that I've seen before include "Profane expressions" , "Solemn vows" , "professions of loyalty" , "Expletives" , "Swearwords" .)

I've seen this clue in The Irish Independent.

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