“Trial” certainly has the “three of” meaning; it is merely very uncommon in most fields, probably because of the other, different-etymology meanings of the word

“Trial” certainly has the “three of” meaning; it is merely very uncommon in most fields, probably because of the other, different-etymology meanings of the word trial and the potential for confusion. https://en.wiktionary.org/wiki/trial#Adjective_2 https://en.wiktionary.org/wiki/trial#Adjective_2 I used “single-licensing” because it felt best; I know of no customary term for it, because it doesn’t tend to need a term. I did also contemplate the alternative “sole-licensing”, sole perhaps matching dual. I’d say “double-licensing” isn’t quite identical in usage to “dual-licensing”: “dual-licensing” is well-established as meaning an OR conjunction, whereas “double-licensing” has been used in some fields as an AND conjunction (that is, for regulation purposes, you must be licensed under two sets of laws in order to practice). I won’t speculate on how much this (important) subtlety is a matter of fundamental meaning of the words and how much it’s customary interpretation of an inherent ambiguity.