All 6 Uses

earnest
in
The Fall of the House of Usher
(Auto-generated)

...he spoke ... of his earnest desire to see me,
*

earnest = sincere or serious
It was thus that he spoke of the object of my visit, of his earnest desire to see me, and of the solace he expected me to afford him.†
For several days ensuing, her name was unmentioned by either Usher or myself: and during this period I was busied in earnest endeavors to alleviate the melancholy of my friend.†

in earnest = serious; or in a serious manner
I lack words to express the full extent, or the earnest abandon of his persuasion.†

earnest = sincere or serious
Shaking this off with a gasp and a struggle, I uplifted myself upon the pillows, and, peering earnestly within the intense darkness of the chamber, harkened—I know not why, except that an instinctive spirit prompted me—to certain low and indefinite sounds which came, through the pauses of the storm, at long intervals, I knew not whence.†

earnestly = sincerely or seriously
The antique volume which I had taken up was the "Mad Trist" of Sir Launcelot Canning; but I had called it a favorite of Usher's more in sad jest than in earnest; for, in truth, there is little in its uncouth and unimaginative prolixity which could have had interest for the lofty and spiritual ideality of my friend.†

in earnest = serious; or in a serious manner

Definitions:

(1) (earnest)
characterized by sincere belief

or:

intensely or excessively serious or determined
(2) (meaning too rare to warrant focus)
Earnest can also be used as a name (variant spelling of Ernest), or to signify the seriousness of a pledge made (as when earnest money is included with an offer to purchase a home).