Another Term for "Long-Thought"

adjectives phrases single-word-requests synonyms

Synonyms to the rescue. The term is Believed to be. The Coelacanth was believed to be extinct until one showed up off the coast of Madagascar.

Related

History of the words "conservative" and "liberal"
Are there specific texts, such as French/English poetry, in which the word romance was originally used, and popularized in?
How to display and set click event on Back Arrow on Toolbar?
Need help with this specific use of "Should" [duplicate]
In terms of databases, is "Normalize for correctness, denormalize for performance" a right mantra?
Does flounder now mean founder?
What's the difference between "have you seen?" and "have you ever seen?"
Using 'for' twice in a small sentence [closed]
Feeling of missing someone [duplicate]
Double present perfect in a compound sentence [closed]
Remove newline character from a string using PHP regex
What is a phrase/word to describe someone who is oblivious to the bad in people