the.com/upright
Vertical in posture, virtuous in character, and the only honest way to play a piano.
means Standing straight up in physical position, or being morally honest and principled in behavior.
from Old English upriht, literally up plus right, meaning straight up — the physical sense stood first, the moral one borrowed the metaphor of standing tall.
Piano senseVertical strings save floor space, sacrifice tone.
Posture to virtueStanding straight became a metaphor for honesty.
Freezer cousinUpright freezers stack like fridges, not chests.