Several parts combine into one character.

The traditional 佛 is a phonetic-semantic compound: 亻 (person) + 弗 (fú, "not / negation" — providing the sound). The character was coined as a transliteration of "Buddha" (Sanskrit बुद्ध) when Buddhism arrived in Han-dynasty China around the 1st century CE. The "Bud-" syllable of Buddha was rendered phonetically using 弗 (fú), with the person radical added to mark "the awakened person." 佛陀 (fótuó) was the full transliteration, with 佛 alone becoming the standard short form. Japan simplified to 仏 (replacing 弗 with the simpler ム-shape); Korea and Mainland China retain 佛.

Korean reading "bul." 佛敎 (bulgyo, Buddhism — Korea's major historical religion, dominant during the Three Kingdoms and Goryeo dynasties), 佛經 (bulgyeong, Buddhist sutras), 佛像 (bulsang, Buddha statue — Korea's national treasures include many bulsang from Silla and Goryeo eras), 南無阿彌陀佛 (Namu Amita Bul, "I take refuge in Amitabha Buddha" — the central chant of Pure Land Buddhism, recited by Korean Buddhists especially before death). Korean Buddhism (Joseon-era 조선 불교) shaped much of Korea's temple architecture, art, and philosophy.

Mandarin fó, 2nd tone. 佛 (fó), 佛教 (Fójiào, Buddhism — historically influential in China since Han dynasty, transformed into Chan/Zen and other distinctly Chinese forms), 佛祖 (Fózǔ, "Buddha-ancestor" = the original Buddha), 拜佛 (bàifó, to worship Buddha / pay respects at a Buddhist temple). 借花献佛 (jièhuā xiànfó, "borrow flowers to offer Buddha") is a common Chinese idiom for "using someone else's gift to make oneself look generous."

Japanese on-readings: ブツ (butsu) — 仏教 (Bukkyō, Buddhism — Japan's second major religion after Shinto, often syncretically practiced together), 大仏 (Daibutsu, "Great Buddha" — referring to massive Buddha statues like Nara's 16-meter Daibutsu at Tōdai-ji and Kamakura's outdoor Daibutsu, both major pilgrimage and tourist sites), 仏壇 (butsudan, Buddhist family altar — present in many Japanese homes for ancestor veneration). フツ (futsu) is rare, surviving in 仏蘭西 (Furansu, France — pre-katakana phonetic transliteration of "France"). Kun-reading ほとけ (hotoke) — 仏 (hotoke, Buddha; also a euphemistic term for the deceased: 仏になる "to become a buddha" = to die, reflecting Pure Land Buddhist beliefs about the dead achieving Buddhahood).

Memory aid: person (亻) + 弗 (sound borrowed for "Bud") — the awakened one, Buddha, transliterated phonetically when Buddhism arrived in China.