| kǔ | bitter/hardship/pain/to suffer/painstaking |
| 苦 | bitter hardship pain |
| 苦丁茶 | broadleaf holly leaf |
| 苦不唧 | slightly bitter |
| 苦不唧儿 | erhua variant of 苦不唧, slightly bitter |
| 苦不堪言 | suffer untold misery; so painstaking that it cannot be expressed in words |
| 苦中作乐 | to find joy in sorrows (idiom); to enjoy sth in spite of one's suffering |
| 苦主 | victim's family (esp. in murder case) |
| 苦乐 | sweet and sour |
| 苦事 | hard job arduous task |
| 苦于 | labor under |
| 苦修 | penance; self-torture |
| 苦况 | wretched state miserable plight |
| 苦刑 | torture corporal punishment (traditionally involving mutilation or amputation) |
| 苦力 | bitter work hard toil coolie (English is loan word), unskilled Chinese laborer in colonial times |
| 苦功 | hard work laborious effort painstaking work |
| 苦劳 | toil hard work |
| 苦参 | liquorice (Sophora flavescens), with roots used in traditional Chinese medicine |
| 苦口 | lit. bitter taste (cf good medicine tastes bitter 良藥苦口|良药苦口) fig. earnestly (of warning, advice) |
| 苦口婆心 | earnest and well-meaning advice (idiom); to persuade patiently |
| 苦口良言 | A bitter mouth utters fine words. |