backbreaking

Mane (Îngilîzî)

Of work, very physically tiring.

Hevwate

arduous

heavy

laborious

gruelling

punishing

toilsome

hard

onerous

exhausting

grueling

operose

ponderous

toiling

tough

unbearable

wearisome

weighted

weighty

labourious

very hard

laboursome

tireful

drudging

excessive

heavy-duty

laboring

labouring

leaden

lumbering

painful

painstaking

plodding

Werger

erschöpfend

ardu

massacrante

arduo

penoso

penoso

ardu

fatigós

feixuc

esgotador

pesat

mühsam

επίπονος

κοπιαστικός

aufreibend

Etîmolojî (Îngilîzî)

From back + breaking.