Etymon
pie-ke-protoindoeuropean-kom-protoitalic-kom-protoitalic-kom-latin-con-protoitalic-katesna-latin-catena-protoindoeuropean-h2-protoindoeuropean-eh2-protoindoeuropean-yeti-protoindoeuropean-eh2yeti-protoitalic-ao-latin-o-latin-cateno-latin-concateno-latin-concatenatus-english-concatenate-from-the-perfect-passive-participle-stem-of-latin-concatenare
A dedicated page for this root is on the way — it will gather every word descended from it, sibling forms across daughter languages, and a branching map of the family tree.