To Spill
To Fall Out
intransitive verb, ichidan verb
This word consists of kanji with hiragana attached. Because the hiragana ends with an う sound, you know this word is a verb.
This is an intransitive verb, so this verb means to spill or to fall out.
こぼれる
Since this word has okurigana (hiragana attached to the kanji) you know that it's probably going to be the kun'yomi reading.
Lucky for you, the kanji readings for transitive and intransitive verbs are almost always the same. Once you learn one, you know them both! This reading is the same as 零す.
おならをした瞬間、目から涙が零れた。
At the moment I farted, a teardrop fell out of my eyes.
ソファに紅茶が零れてるんだけど！誰が犯人だ？
Someone spilled tea on the couch! Who's the guilty one?
窓から美しいメロディが零れてきた。
A beautiful melody spilled out from the window.