Solid Opal

The label says white; the yellow cast is what makes this one specific rather than generic. Behr's designation for it is BWC-06.

Chroma 4.3 is the whole difference: below four a color reads as grey, above ten the yellow cast takes over. At this LRV (83.0), the wall itself becomes a light source of sorts, reflecting daylight back into the room rather than absorbing it.

The yellow cast in this white is the part that moves most under different light; the white itself barely changes, but that undertone will. A dependable choice for small rooms, hallways, and anywhere natural light is limited.

Eggshell is a reasonable step up from flat if the room needs to hold up to cleaning, without adding much visible sheen.

PPG Linen Ruffle (1075-1) matches it closely enough that no one will tell them apart on a wall. This is not a rare shade: 8 colors from other brands sit within delta-E 2 of it.

It is lighter than 92 percent of the Behr range. Behr lists it in the BWC codes, alongside 29 other colors.