High resolution image: https://commons.wikimedia.org/wiki/File:Bulbophyllum_ipanemense_2023_Hortus_Botanicus_Leiden.jpg

In biology, there is the operator × that is used to denote hybrids between species. In fact, this operator is more mathematical than it seems, because it can be analysed mathematically: It is idempotent, commutative and associative. It gets interesting when we consider orchid hybrids: They use a slightly different "×" which is not associative. A blog article about this is here: https://networkscience.wordpress.com/2023/04/26/how-names-of-hybrid-orchids-work/