pekʷ-
“to cook, to ripen”cook, ripen
Root for cooking and ripening. Yields Latin coquere, English "cook", Greek peptein "to digest".
Discussion
*pekʷ- is a Proto-Indo-European root meaning "to cook" or "to ripen," one of the key culinary and agricultural roots of the proto-language.
Latin coquere "to cook" (with the characteristic PIE *p > Latin *kʷ > c/qu pattern via assimilation to the following labiovelar) yields English cook, kitchen (via Latin coquīna), cuisine (via French), biscuit ("twice-cooked"), and concoct. Greek péptein "to digest, to cook" (with *kʷ > p) gives English peptic, pepsin, and dyspepsia.
Sanskrit pácati "cooks" preserves the root most transparently. The Sanskrit form shows the original *p- initial without the Latin assimilation. Old English āfigen "fried" (from a related Germanic form) is sometimes connected.
The dual meaning "to cook" and "to ripen" reflects the PIE conceptual equation between artificial and natural maturation—cooking transforms raw food as ripening transforms unripe fruit. This connection is preserved in English: a dish "done" and fruit "done" use the same metaphor.
The Latin assimilation of *p...kʷ to *kʷ...kʷ (giving coquere rather than expected *poquere) is a textbook example of long-distance assimilation. Modern descendants include English cook, kitchen, cuisine, concoct, biscuit, precocious ("pre-cooked/early-ripened"), and peptic.
Notes
Also source of "peptic", "concoct", "precocious"