1.Petrichor (n.)

Definition: a pleasant smell that frequently accompanies the first rain after a long period of warm, dry weather

Sentence: She could taste the petrichor in the air as the rain blessed the cracked lips of the earth.

2.Brumous (adj.)

Definition: foggy; wintry; misty

Sentence: The air hit him, brumous and chilly, as he opened his front door and waved down the nearest taxi cab.

3.Syzygy (n.)

Definition: a conjunction or opposition, especially of the moon with the sun; a pair of connected or corresponding things

Sentence: The moon and the sun were in perfect syzygy during the eclipse and it seemed that all the world had paused, breath held carefully in awed lungs.

4.Sonder (n.)

Definition: the realization that each random passerby is living a life as vivid and complex as your own

Sentence: The sonder swelled and moved within her and she paused on the sidewalk and peered, in reverence, into the faces of the strangers that no longer melded and blended together, but were now each beautifully unique and distinct.

5.Hiraeth (n.)

Definition: a longing or nostalgia, especially for things Welsh; a homesickness, a bond with one’s home country when one is far away from it

Sentence: As the boat sounded its parting cry, she felt the hiraeth rise up and threaten to overwhelm her as she watched the green shores of Wales be slowly swallowed whole by endless blue of the sea.

6.Lagniappe (n.)

Definition: something given as a bonus or extra gift

Sentence: He quietly passed her a small envelope and told her, smirking mysteriously, to just consider it a small sort of lagniappe.

7.Kenopsia (n.)

Definition: the eerie, forlorn atmosphere of a place that’s usually bustling with people but is now abandoned and quiet

Sentence: The empty subway station cast a sort of kenopsia over the pallor of the white tiles and the blank spaces of the time-worn benches.

8.Vellichor (n.)

Definition: the strange wistfulness of used bookstores, which are somehow infused with the passage of time — filled with thousands of old books you’ll never have time to read, each of which is itself locked in its own era

Sentence: He could smell the vellichor, swirling, curling, twisting through every page, every letter of the tattered and the broken books that nobody cared to open, that nobody wanted anymore.

9.Opia (n.)

Definition: the ambiguous intensity of looking someone in the eye, which can feel simultaneously invasive and vulnerable

Sentence: The opia of the moment was palpable as she stared, a threatened animal, into his cold predator eyes that gazed, somewhat amused, back at her.

10.Pyrrhic (adj.)

Definition: a victory won at too great a cost to have been worthwhile for the victor

Sentence: It was a pyrrhic victory, won with sweat and blood and tears blinding eyes and many empty bodies that would not make the trek home.

Citations:

"Oxford Dictionaries - Dictionary, Thesaurus, & Grammar." Oxford Dictionaries - Dictionary, Thesaurus, & Grammar. N.p., n.d. Web. 10 May 2016.

Koenig, John. "The Dictionary of Obscure Sorrows." Tumblr. N.p., 2009. Web. 13 May 2016.

"Dictionary.com - The World's Favorite Online English Dictionary!" Dictionary.com. N.p., n.d. Web. 10 May 2016.

"Encarta Dictionary (Online College Dictionary) - Read the Full Review." Encarta Dictionary (Online College Dictionary) - Read the Full Review. N.p., n.d. Web. 10 May 2016.

"Urban Dictionary." Wikipedia. Wikimedia Foundation, n.d. Web. 10 May 2016.