佛陀 (fó tuó) is the Chinese transliteration of the Sanskrit word 'Buddha', meaning 'the Awakened One' or 'the Enlightened One'. Unlike the more common Chinese word 佛 (fó), which can refer broadly to Buddhas, Buddhist images, or even deified beings in folk contexts, 佛陀 specifically denotes Siddhartha Gautama—the historical founder of Buddhism—or the ideal of full enlightenment itself. The character 佛 carries the core meaning of 'enlightened being', while 陀 is a phonetic loan used solely to approximate the final syllable '-dda' in Sanskrit; it contributes no independent meaning.

This term is formal and reverential, frequently appearing in classical Buddhist texts, academic discussions, temple inscriptions, and respectful speech. It emphasizes the human teacher and his awakened state rather than iconography or ritual function. Learners should note that 佛陀 is rarely used in casual conversation—native speakers typically say 佛 or 释迦牟尼佛 when referring to the historical Buddha—and it almost never appears in compound words like 佛教 (Buddhism) or 佛像 (Buddha statue).