smile

noun

1. A facial expression comprised by flexing the muscles of both ends of one's mouth, often showing the front teeth, without vocalisation, and in humans is a common involuntary or voluntary expression of happiness, pleasure, amusement, goodwill, or anxiety.

   “She's got a perfect smile.”

   “He has a sinister smile.”

   “She had a smile on her face.”

   “He always puts a smile on my face.”

   “Then came a maid with hand-bag and shawls, and after her a tall young lady.[…]She looked around expectantly, and recognizing Mrs. Cooke's maid[…]Miss Thorn greeted her with a smile which greatly prepossessed us in her favor.”

2. (figuratively)Favour; propitious regard.

   “the smile of the gods”

3. (dated, slang)A drink bought by one person for another.
4. (abbreviation, alt-of, uncountable)Abbreviation of small incision lenticule extraction: corrective eye surgery in which a femtosecond laser photodisrupts ("carves") a lenticule of tissue within the corneal stroma that is then extracted through a small arc-shaped incision in the side of the cornea.

verb

1. (ambitransitive)To have (a smile) on one's face.

   “When you smile, the whole world smiles with you.”

   “I don't know what he's smiling about.”

   “She smiles a beautiful smile.”

   ““[…] This is Mr. Churchill, who, as you are aware, is good enough to come to us for his diaconate, and, as we hope, for much longer; and being a gentleman of independent means, he declines to take any payment.” Saying this Walden rubbed his hands together and smiled contentedly.”

   “Once I was a young man / And all I thought I had to do was smile”

2. (transitive)To express by smiling.

   “to smile consent, or a welcome”

   “Mr Carlyle smiled his indulgence privately. "My dear chap, you mustn't let your retentive memory of obscure happenings run away with you," he remarked wisely.”

   “I had occasion […] to make a somewhat long business trip to Chicago, and on my return […] I found Farrar awaiting me in the railway station. He smiled his wonted fraction by way of greeting, […], and finally leading me to his buggy, turned and drove out of town. I was completely mystified at such an unusual proceeding.”

3. (intransitive)To express amusement, pleasure, or love and kindness.

   “When last I saw thy young blue eyes, they smiled.”

4. (intransitive)To look cheerful and joyous; to have an appearance suited to excite joy.

   “The sun smiled down from a clear summer sky.”

5. (intransitive)To be propitious or favourable; to countenance.

   “The gods smiled on his labours.”

6. (intransitive)Of ackee fruit: to open fully, indicating that it is no longer toxic, and ready to be picked.

   “The fruit looks a bit like a large pink mango or guava, until it has ripened. Then it “smiles,” bursting open, exposing yellow meat with black seeds.”