Words to describe those in-between, stuck in the middle, between the devil and the deep blue sea, liminal kinds of things.
— Read on www.merriam-webster.com/words-at-play/in-betweens-words-and-phrases/liminal
As a quality professional I can use threshold, interstice and even liminal and occasionally be-twixt. But now I need to be ‘between the devil and the deep blue sea’ more often at quality management reviews and the visual management boards.