puppy love
noun phrase

- romantic love that a young person feels for someone else, which usually disappears as the young person becomes older

Cambridge Dictionary

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Most people, except for the really cold-hearted among us, adore puppies. There is an irresistible attraction. Upon first sight, we feel helplessly in love. And they make us resort to baby talk by blurting out things like "coochie coo, awwww" and other unintelligible expressions. We love puppies - and that's why puppy love describes that feeling of infatuation that young people experience when they fall in love or have a crush on someone.

In the 1960s, at the height of the teenage love song craze in the US, teen idol Paul Anka released a song called Puppy Love that reached number 2 on the charts:

And they called it puppy love
Oh, I guess they'll never know
How a young heart really feels
And why I love her so

The term puppy is of uncertain origin but it may be from the Middle French poupée (doll, toy, puppet). The meaning shifted from "toy dog" to "young dog" in the late 16th century and replaced the Middle English whelp (related to the German Welpen), which today is mainly used as a biological term.

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SYNONYMS

calf love, crush, first love, infatuation, young love