Why Indet for some families?

In some cases, if you enter a family name, the English name comes up as “Indet.” E.g. Beetle | Observation | UK and Ireland | iSpot Nature
Same for Coccinellidae - indet. ladybird. Whereas if you identify something as Tipulidae, it is just called a cranefly. So does anyone know why some families get the indet. treatment, and what exactly does it mean? Is it indetermined, meaning not yet identified further, in which case shouldn’t it be undet? Or is it indeterminable, meaning can’t be identified further? In which case I still think undet. would be more correct.

To explain why it’s indet. rather than undet., I think it likely that it is a carry-over from the use of Latin in natural history - “sp. indet.” is the abbreviation for “species indeterminatus”.

As for the inconsistency in its use or non-use for vernacular names of families, I’d ascribe that to the dictionary being a compendium of different sources from people with different usage practices.

Yes, it’s been here from the beginning - indeterminate
It is a fave of a few early iSpotters and Mick Talbot has a lot!
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