1Potential form of 'say': to be able to say or to be possible to state something.
その事実は誰にもはっきり言えることではない。
That fact isn't something you can clearly tell anyone.
真実は言えるが、今は言わない方がいい。
I can tell the truth, but it's better not to say it now.
君には気持ちを正直に言える人が必要だ。
You need someone you can honestly talk to.
2Archaic/literary usage meaning 'said' or 'have said' (often seen in phrases like 言えるごとく). Mainly found in classical or literary contexts.
古い文献に『言えるごとく』という表現が見える。
In old texts you can see the expression '言えるごとく'.