lengthily

In a lengthy way, in a manner that is long and drawn out, especially in time.

Japanese Meaning

長々と / 冗長に / くどくどと

The professor spoke lengthily about the historical causes of the war during the entire lecture.

教授は講義の間ずっと戦争の歴史的原因について長々と話した。

Sense（1）

In a lengthy way, in a manner that is long and drawn out, especially in time.

more lengthily

（ comparative ）

most lengthily

（ superlative ）