Englishnigh
adverb
□ nigh on
highlights are nigh-on impossible to pick out:
well-nigh, almost, nearly, just about, more or less, practically, virtually, all but, as good as, next to, close to, near, to all intents and purposes, approaching, bordering on, verging on, nearing, about;
roughly, approximately;
not quite;
informal pretty nearly, pretty much, pretty well.
nigh Oxford Dictionary of English