I. fail ‧ ing 1 /ˈfeɪlɪŋ/ BrE AmE noun [countable]
[ Word Family: noun : ↑ fail , ↑ failure , ↑ failing ; adjective : ↑ failed , ↑ unfailing ; verb : ↑ fail ; adverb : unfaillingly]
a fault or weakness:
I love him, despite his failings.
II. failing 2 BrE AmE preposition
failing that/this used to say that if your first suggestion is not successful or possible, there is another possibility that you could try:
We will probably have the conference at the Hyatt Hotel or, failing that, at the Fairmont.