Avocado follows Nahuatl āhuacatl through Spanish aguacate and a later reshaping. Guacamole preserves a whole Nahuatl compound: āhuacatl, “avocado,” plus mōlli, “sauce.” Color exposes those two elements in the final word without changing its spelling.

Sources: Merriam-Webster, avocado and guacamole; Online Etymology Dictionary, avocado and guacamole.

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Dates follow the earliest cited evidence for the form and sense shown. Notes name the sources. Timeline spacing is compressed; undated stages are placed in sequence.