i-adjective
difficult to say; hard to bring up
Used when a topic is emotionally or socially awkward to mention, not for physical difficulty speaking.
本当のことを言うのは言い辛い。
It's hard to say the truth.
彼にはお金の話が言い辛い。
It's difficult to bring up the topic of money with him.
Almost synonymous, but 言い辛い emphasizes emotional or social awkwardness, while 言いにくい can also refer to physical difficulty in pronouncing or phrasing.
Compound of 言い (stem of 言う 'to say') and 辛い (suffix meaning 'difficult to do').