This idea is intimately tied to the name Deborah, far more than any other name is associated with any other dimensionless number such as the Reynolds number, the Prandtl number, or the 2nd Domköhler number, all of which are named after researchers. Instead with the Deborah number, it is named after a person that is long deceased for over 3000 years and obviously not a rheologist. The Book of Judges in the Bible has the victory song that the prophetess Deborah wrote after she gave the Canaans a good a**whooping on the battlefield. One line of that song is "The mountains flow before the Lord", which a prominent rheologist (Marcus Reiner) thought captured this concept perfectly. On the observation scale of God, mountains could appear to flow like a liquid, while for people and their short observation times, the mountains appear very solid. And so the name of this dimensionless number is "Deborah".
Reiner described this line of thought in an article (open access) published in 1964, in which he also further describes the relationship between "rheology" and "theology". Since that time, the relationship has been further blurred by spellcheckers. The first time someone tries spelling "rheology", the spellchecker doesn't recognize the word and instead suggests "theology" as a correct word. (Not that bad a choice, as the "r" and the "t" are adjacent on the QWERTY keyboard.)
Steve Carrington of Malvern Instruments however, has proposed yet the latest connection between the two subject this last week:
"How many times have you looked at some rheological data....and hoped for some divine intervention to help you understand it?!?"
More times than I ever imagined. More times...