to bud; to sprout (as plants).
春になると庭の木々が萌える。
In spring, the trees in the garden bud.
新緑が萌える季節が一番好きだ。
I like the season when fresh green leaves sprout the most.
colloquial: to be infatuated with or to have a crush on someone/something (often used about fictional characters); to feel strong attraction or 'moe'.
彼の優しい笑顔に完全に萌えた。
I totally fell for his gentle smile.
そのアニメのサブキャラに萌える人が多い。
Many people feel 'moe' for that anime's supporting character.
この表現は若葉が萌える様子を描いている。
This expression depicts the way young leaves bud.