that is to say
Definitions
Used to introduce a clarification or more precise explanation of a previous statement.
Used to rephrase or elaborate on what has just been said.
Examples
The project is behind schedule, that is to say, we will not meet the original deadline.
He is a polyglot, that is to say, he can speak more than five languages fluently.
Synonyms
in other words namely specifically to put it another way which is to say
Antonyms
conversely on the contrary in contrast however nevertheless nonetheless