suffer

(flowertop) + (old)
★★★☆☆
8 strokes

Onyomi

KU

as in, 'My KUCHI ( 口 ) was suffering from too much candy. '

Mnemonic

The old flower was suffering : wilting, turning brown, being eaten by aphids.

Kunyomi

にが*い bitter taste ー medicine, okra. Can also be used figuratively - the bitter taste of defeat.
★★★☆☆
( ) くる*しい adjective describing mental suffering - which is caused BY 痛み (physical pain). i.e. 'My throat is 痛い、 so talking or swallowing is 苦しい’
★★★☆☆
( xxxに ) くる*しむ to hurt or suffer from XXX
★★★☆☆

Jukugo

苦労(くろう)

hardships ★★★☆☆
(suffer) + (labor) = 苦労 (hardships)

xxxは 苦手(にがて)

this is not my thing! ★★★☆☆ KUNKUN
(suffer) + (hand) = 苦手 (this is not my thing!)

this has 2 meanings. One is "I'm not good at this" and the second is "I don't like this" Clever Japanese!

苦情(くじょう)

a grievance or complaint ☆☆☆☆☆
(suffer) + (emotion) = 苦情 (a grievance or complaint )

Synonyms

bad point
苦手    欠点    弱点    欠陥   
bad-tasting
まずい 酸っぱい    苦い    渋い   
complaint
愚痴    文句    クレイム 苦情   
pain or suffering
痛い    苦しい    悲しむ    苦しむ