These are words that have lost their meanings over time and can't be reconstructed from context, as it only appeared in that context once and not in others. I've searched with Google but came up empty. I tried searching the OED for "unknown origin", but that returns none of them, just words like dog or bigot, whose meanings are known but whose exact origins are lost.
A search for hapax legomena in English took me straight to https://en.wikipedia.org/wiki/Hapax_legomenon#English_examples
As for ones that have lost their meaning, it is inevitable, given the uncertainty about these words that there is always some degree of dispute about whether the meaning is unambiguous or not. There will always be some who say "this clearly means x" and others that say "the meaning is not certain". This can be seen from the range of examples in both English and other languages. Thus, although this is a list of some hapaxes, I don't think it is possible to provide a list specifically of "hapax legomena that have lost their meaning over time", and indeed many will have had meanings originally but some could have been erroneous to start with or be transcription errors.