In Hindu cosmology, particularly long periods of time are reckoned in terms of units like "days of Brahma", where one day of Brahma is equal to 4.32 billion "human" years.
I always thought that the "Brahma" here was Brahma as in the creator deity of the Trimurti. However, in another answer, it is claimed that this is actually Brahman, the supreme being that underlies all. Which of these is correct?
My thinking in associating this with the Trimurtic Brahma was that it is said the universe is remade on each day of Brahma, and so the association with Trimurtic Brahma makes sense, since he is the one that does the remaking.