The phrase "yellow undertones" refers to a subtle hint or color that can be seen within light or fair skin. It means that there is a tinge of yellow coloring beneath the surface of the skin. Full definition
Cool tones never looked quite right on me and I discovered I was actually a warm toned girl with yellow undertones in my skin! (thestyleventure.com)
If you're a pink lover and looking for a pink lipstick shade then Pink Petal from Maybelline can be your choice as it is a soft pink color with yellow undertones in it. (stylecraze.com)
Neutralize the look of yellow undertones and sallowness on light to medium skin tones with a purple or lavender - colored concealer. (skincare.com)