Liveliness!

soporific
(adj)
soh-pǝ-RIF-ic
Meaning

sleep-causing

1st Sample Sentence

I fell asleep about five minutes into the professor's soporific lecture.

Root

sopor soporis (deep sleep) (Latin)

Antonyms

riveting

Mnemonics

Sounds like : so poor fiction. And poor movies make us feel sleepy