threshold · noun /ˈθreʃ.həʊld/
threshold
C2 C the level at which something starts to happen
Dictionary example:
He had a low boredom threshold.
Learner example:
That night...that night - yet another one spent together online turned [out] to be the final threshold. (Certificate of Proficiency in English; C2; Polish)
on the threshold of sth
C2 at the start of a new and important time or development
Dictionary example:
We're on the threshold of a new era in European relations.
Learner example:
On the threshold of the third millen[n]ium, there is no stopping progress. (Certificate of Proficiency in English; C2; French)
