(noun) An object designed to open and close a lock.
"Change is the key to unlocking growth."
"Patience is a key element of success."
"Success isn't the key to happiness. Happiness is the key to success."
"The key for us, number one, has always been hiring very smart people."
"Inner peace is the key: if you have inner peace, the external problems do not affect your deep sense of peace and tranquility."
"One year can change the courage of your entire life. Patience & hard work is key."
"A smile is often the key thing. One is paid with a smile. One is rewarded with a smile. One is brightened by a smile. And the quality of a smile can make one die."
"Letting go is a key to unlock positive energy."
"No Expectation is the key to happiness and peace."