To begin to say something that had not been said before; to start mentioning previously unspoken thoughts or feelings.
彼は黙っていたが、やがて過去の失敗について言い始めた。
He was silent, but eventually began to talk about past mistakes.
彼女は初めて本音を言い始めたので、皆が驚いた。
She began to speak frankly for the first time, so everyone was surprised.
会議でその問題について言い始めたのは田中さんだった。
Tanaka was the one who started talking about that issue in the meeting.
To start saying something; to begin speaking (more generally — marking the start of verbal expression).
部長が新しい方針について言い始めると、室内が静かになった。
When the manager began to talk about the new policy, the room fell silent.
赤ちゃんが『ママ』と言い始めたのはこの週末だった。
The baby started saying 'mama' this weekend.
彼は『実は…』と言い始めて、長い説明をした。
He began with 'actually...' and gave a long explanation.
To begin to court or address someone with romantic intent — a somewhat old-fashioned or literary use similar to 'to make advances'.
昔、この村では若者が気に入った娘に言い始める習慣があった。
In the past, in this village young men had the custom of beginning to court a girl they liked.