onerous
/ˈɒnərəs/adjective
1- (of a task, duty, or responsibility) involving an amount of effort and difficulty which is oppressively burdensome（任务、责任等）繁重的; 费力的; 困难的：
he found his duties increasingly onerous.
他发现自己的职责越来越繁重了。
1.1
- Law involving heavy obligations【律】义务沉重的：
an onerous lease.
义务沉重的租赁。
派生词
onerously
adverbonerousness
noun词源
late Middle English: from Old French onereus, from Latin onerosus, from onus, oner- 'burden'.