Smile (noun) – la sonrisa
(Pronounced son-ree-sah)
To remember that smile is pronounced son-ree-sah (sonrisa) in Spanish, use the following mnemonic:
Her smile and song are the reason I'm so happy (sonrisa).

Sonrisa is feminine, so it's la sonrisa. Imagine a lady painting a smile on her face.

Examples of sonrisa (smile) in a sentence
Tu sonrisa me alegra el día.
(Your smile brightens my day.)
Ella tiene una sonrisa muy bonita.
(She has a very pretty smile.)
La sonrisa de un niño es contagiosa.
(A child's smile is contagious.)