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chill - chill out /tʃɪl/ - /aʊt /
verb
informal - slang - calm down and relax: I can lean back and chill | chill out, okay?
• pass time without a particular aim or purpose, especially with other people:
we had a week at home and we chilled out.
1 to calm down or relax. (often used with out)
2 to pass time idly; loiter. (often used with out)
3 to keep company; hang out. (often used with out)

On an interesting side note,
chill (out) has encountered such widespread usage that it has created the expression:
What are you gonna do tonight? Netflix and chill - see a movie and relax.

chill4chil2

chill out /tʃɪl/ - /aʊt /
adjective
suitable for relaxation after energetic dancing or hard work: a chill-out area in a club or disco, chill-out music

Last week's word

dude
/duːd/
Dude is a slang greeting term between men, meaning "guy" or "man." For example: "Dude! So, like, what's up?" It's been popularized by movies and TV shows, and has a distinctive whiff of American West Coast hippie culture to it.
In the American nineteenth century dude had another life as a term for a dandy — a particularly well-groomed and fancily-dressed young man. From this came the term of dude as meaning a big city dweller unfamiliar with the ways of the Wild West. When such types came out West to enjoy the rugged life, they stayed in "dude ranches," basically resorts or spas, not real working ranches, and the term is still around today.

dudecool dude
dude /duːd/
noun (informal, mainly North American)
a man; a guy: if some dude smacked me, I'd smack him back.
• a stylish, fastidious man: cool dudes.
• US a city-dweller, especially one vacationing on a ranch in the western US.

verb [no object]
dude up
dress up elaborately: my brother was all duded up in his new tux.

ORIGIN
late 19th century (denoting a dandy): probably shortened from
doodle, perhaps with allusion to Yankee Doodle Dandy.