诉苦
sù kǔ · HSK 7
to complain
🗣️ 诉苦 = 诉 (tell) + 苦 (bitter) = to tell of your bitterness, i.e. complain
诉 means to tell or relate, and 苦 means bitter or hardship. Putting them together gives the act of relating your hardships to someone, which is grumbling or airing a grievance.
苦 — grass radical 艹 + 古 (old)
Originally referred to a bitter-tasting plant, with the grass radical 艹 indicating its botanical nature and 古 providing the phonetic element. The meaning extended from the literal bitter taste to figurative senses of hardship, suffering, and painful effort.