Noncoding RNA (ncRNA) and long noncoding RNA (lncRNA) are scientifically invalid terms because they define molecular entities according to properties they do not possess and functions they do not perform. Here, I suggest retiring these two terms. Instead, I suggest using an evolutionary classification of genomic function, in which every RNA molecule is classified as either "functional" or "junk' according to its selected effect function. Dealing with RNA molecules whose functional status is unknown require us to phrase Popperian nomenclatures that spell out the conditions for their own refutation. Thus, in the absence of falsifying evidence, RNA molecules of unknown function must be considered junk RNA (jRNA).
@article{arxiv.1709.01429,
title = {Down with ncRNA! Long live fRNA and jRNA!},
author = {Dan Graur},
journal= {arXiv preprint arXiv:1709.01429},
year = {2017}
}