Usage note: low gear implies the first sense, a low gear implies the second.

To discourage sexual attraction between brothers and sisters-in-law, later Jewish law expressed a clear preference for ḥalitzah (the ritual of the sandal) rather than levirate marriage.

So the issue of unification only comes up when the geometry can no longer be treated as a mere background, or conversely, when the classical theory is no longer accurate. But these circumstances exist (as far as we know) in only two places: the earliest moments of the Big Bang, and the immediate vicinity of singularities hidden behind black hole event horizons.

Sit downe by her: adorned with my Crowne, As if thou wert the Empreſſe of the world.