yellow (of a person)
adjective

A yellow person is someone who who shows fear or timidity.

Why does calling someone "yellow" mean cowardly?

Before the United States'Civil War, there were two opposing sides on the issue of slavery. As the debates between these two groups continued, agitators on both sides published anonymous pamphlets and flyers which attacked public figures.

These unsigned publications, which typically contained vicious lies and rumors, were usually printed on cheap, unbleached paper that had a yellow tint. When it was learned certain newspaper editors were contributing to the publishing effort, the practice became known as "yellow journalism."

Eventually, the term "yellow" became known as a cowardly act.

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SYNONYMS

cowardly, chicken, chicken-hearted, lily-livered, white-livered, yellow-bellied, cowering, cringing, craven, faint-hearted, timid, poor-spirited, unmanly

You may also hear a yellow person being called a:

shrinking violet, a waverer, a vacillator, a hesitator

And finally, become a "yellow expert" by knowing these other common uses of this colourful adjective:

yellow plum - die Mirabelle
Yellow Star - der Judenstern
yellow pages - das Branchenbuch
yellow boletus - der Steinpilz
yellow journal - das Revolverblatt
yellow of an egg - das Eigelb
yellow mica [min.] - das Narrengold
yellow fever [med.] - das Gelbfieber
yellow lines - gelb markierte Bordsteine (No Parking!)
yellow dog contract - (Am:) Arbeitsvertrag mit der Verpflichtung, keiner Gewerkschaft beizutreten