adverb
each; respectively; individually
Describes multiple people doing something separately or each in their own way, often with a sense of acting without coordination. Common in phrases like てんでに~する.
みんながてんでに好きなことを言い始めた。
Everyone started saying whatever they wanted, each in their own way.
彼らはてんでに帰っていった。
They each went home separately.