Definitions

Liminal  lim·i·nal  |  /ˈlimənl/

1.  Of or pertaining to an entrance or threshold. (from late 19th c.)
2.  Of or pertaining to a beginning or first stage of a process. (from late 19th c.

  Synonyms: inceptive, inchoative, marginal, transitional

Seminal  sem·i·nal  /ˈsemənl/

1.  Of or relating to seed (or semen)
2. Creative or having the power to originate.
3. Highly influential, especially in some original way, and providing a basis for future development or research.

 Synonyms: influential, pioneering
   
    "The Structure of Scientific Revolutions" was a seminal work in the modern philosophy of science.

Subliminal  sub·​lim·​i·​nal  | /səˈblɪmɪnəl/

1.     (of a stimulus) Below the threshold of conscious perception, especially if still able to produce a response.

doggerel   dog·​ger·​el | \ ˈdȯ-g(ə-)rəl

1. (poetry) Of a crude or irregular construction. (Originally applied to humorous verse, but now to verse lacking artistry or meaning.)

References

• Primer on Subliminal Messaging 
• Bojack Horseman is Seminal? 
• Living in Liminal Times

Doggerel
My attempt at a couplet(?) using some of this week's vocabulary:
The episode prep was minimal
because the year-end time is liminal
and the topic we cover aint super-seminal
I'll leave you with verse not subliminal
all wrapped up in this here doggerel