New World Encyclopedia defines what a yarmulke is.
"Yarmulke," New World Encyclopedia, accessed December 3, 2021
A 'yarmulke (Hebrew: יאַרמלקע meaning "cap") is a thin, slightly-rounded skullcap traditionally worn by Orthodox Jewish men, although some men and women in the egalitarian Conservative and Reform movements also wear it during services. Wearing a Yarmulke is described as "honoring God."[1] According to the Talmud, a Jewish man is required to cover his head during prayer.[2] The Yarmulke has become identified as a symbol of Judaism over the last century. It is also known as a kippah (Hebrew: כִּפָּה kippa, plural kippot .קאַפּעלע kapele.)
Many religions imbue clothing with religious significance as a sign of respect before God. Religious vestments convey the message that daily practice requires purity and cleanliness as well as constant remembrance of the divine's blessings and commandments.