What does clade mean?
A clade is a group of organisms that consists of a single common ancestor and all of its evolutionary descendants — in other words, one complete 'branch' on the tree of life. The term, coined by biologist Julian Huxley in 1957 from the Greek 'klados' meaning branch, is central to modern taxonomy and phylogenetics because it captures genuine evolutionary kinship: birds, for instance, sit within the dinosaur clade despite looking nothing like Tyrannosaurus rex. What makes a clade distinct from an ordinary category is completeness — a true clade cannot exclude any descendants, which is why scientists sometimes reject familiar groupings (like 'reptiles') that leave out related lineages. The word appears mainly in scientific writing, alongside related terms such as cladistics and cladogram, but it has become increasingly visible in popular science as our understanding of evolution deepens.
nounA group of organisms descended from a single common ancestor, including all of that ancestor's descendants; a monophyletic branch on a tree of evolutionary relationships.
- A group of organisms consisting of a common ancestor and all its evolutionary descendants (a monophyletic group), used in biological classification.
"Birds and crocodiles belong to the same clade, sharing a common ancestor more recent than either shares with lizards."
"Modern phylogenetics recognizes birds as members of the dinosaur clade."
"Researchers used DNA sequencing to determine which species belonged to the same clade."
Standard pluralization; simply add -s.
"The analysis identified three major clades within the genus."
The word 'clade' was only coined in 1957 by Julian Huxley, yet it rewired how scientists name life itself — because if evolution is real, a group that excludes some descendants isn't a family at all.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of clade
'Clade' derives from the Ancient Greek 'klados', meaning 'branch' or 'shoot'. It was coined in 1957 by the biologist Julian Huxley as a convenient term for what earlier researchers had called a 'natural group' or 'holophyletic group'. Its relatives include 'cladistics' and 'cladogram', terms central to the method of classifying organisms strictly by shared ancestry.
How clade is actually used
'Clade' belongs primarily to scientific registers — evolutionary biology, systematics, and phylogenetics — though it has spread into popular science writing. It carries a precise technical meaning: unlike 'group' or 'family', it implies strict monophyly, so calling something a clade asserts a specific claim about shared ancestry. It is not used in everyday conversation outside science contexts.