'Let' is a verb and a noun. It has two meanings as a verb, only one as a noun. All three meanings can end in the letter 's': lets. Also, one of the verbs takes a possessive: "Let's". Find out more about Let vs Let's.
This poem by Edward Lear goes by several other titles too:~ The Owl and the Pussycat Poem~ Owl and the Pussycat Poem~ The Owl and the Pussy-cat Verse IThe Owl and the Pussy-cat went to seaIn a beautiful pea-green boat,They took some honey, and plenty of money,Wrapped up in a