| Idiom | Meaning | Example | 
| sicker than a dog | 
very, very sick; as sick as a parrot
 | 
He wants to go and play hockey, and he's sicker 'n a dog!
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| sicko | 
weird person, pervert, psycho, scumbag
 | 
"Who would pour ketchup all over my car?" "Oh, some sicko, I guess."
 | 
| side by side | 
standing/walking beside, shoulder to shoulder
 | 
The children were standing side by side on the stairs.
 | 
| sight for sore eyes | 
(See a sight for sore eyes)
 | 
 | 
| sign in | 
sign your name to show you are in the building
 | 
Be sure to sign in. We want to know that you are safe inside.
 | 
| sign off | 
say goodbye, close, stop writing or talking
 | 
"I'll sign off now, but I'll write again soon. With love, Kim."
 | 
| sign out | 
sign your name to borrow something, on loan
 | 
If you want to sign out a book you will need a library card.
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| sign up | 
sign the list, enrol, enlist
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"Did you sign up for lessons?" "Yes. My name is on the list."
 | 
| silence is golden | 
silence is wonderful,  silence is peaceful
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After a day of teaching grade two students, silence is golden.
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| silkhead | 
bald person, chromedome
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If you were a silkhead, would you wear a toupee?
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