形容詞 incessant:

1. occurring so frequently as to seem ceaseless or uninterrupted
   同義詞：perpetual, endless
2. uninterrupted in time and indefinitely long continuing
   同義詞：ceaseless, constant, never-ending, perpetual, unceasing, unremitting

1. Incessant background music makes me punch-drunk after a couple of hours.
   接連聽了幾個(gè)小時(shí)的背景音樂，使我覺得昏昏沉沉。
2. That incessant background music gets on my nerves.
   那沒完沒了的背景音樂令我非常煩惱！
3. The jukebox ground out an incessant stream of pop music.
   自動電唱機(jī)沒完沒了地放送流行樂曲。
4. We are tired of his incessant complaining.
   我們對他沒完沒了的埋怨感到厭煩。

in.ces.sant

adj.（形容詞）
Continuing without interruption.See Synonyms at continual
連續(xù)不斷的參見 continual

來源：
Middle English incessaunte
中古英語 incessaunte
from Late Latin incess3ns incessant-
源自 后期拉丁語 incess3ns incessant-
Latin in- [not] * see in-
拉丁語 in- [不] *參見 in-
Latin cess3ns [present participle of] cess3re [to stop] * see cease
拉丁語 cess3ns [] cess3re的現(xiàn)在分詞 [停止] *參見 cease

【引伸】
inces.sancy
n.（名詞）
inces.santly
adv.（副詞）