How many letters does the top answer for “in a lasting manner; with long continuance.” have?

The most common answer is durably (7 letters).

Crossword clue: in a lasting manner; with long continuance.

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

durably 7 letters web-def

In a lasting manner; with long continuance.

of long continuance; lasting. milton. 60% similar → diuturnal

in a lasting manner. 50% similar → lastingly

in a slowly developing and long lasting manner 50% similar → chronically