Saying that the poem "The Jabberwocky" is absurd is true, but calling it a work of the absurd, or absurdist fiction, is a little risky. Works of the absurd are generally more satirical and focusing on human nature, which is not the point of Carroll's "The Jabberwocky". However, there are a few things this poem has in common with absurdist fiction: lack of plot, lack of moral, and the form. Absurdist fiction often has no real structure or plot, which Carroll's poem is also lacking; there is a slight plot (the Jabberwocky is bad, a guy decapitates it, and then the guy goes home), but nothing too elaborate or really firm. It also has no moral; it is not trying to tell you that you should slay evil creatures, it is not trying to tell you anything, except maybe to "Beware the JubJub bird, and shun the frumious Bandersnatch!" Also, absurdist fiction can often be found in the form of a poem, which is what "The Jabberwocky" is.
All of that being said, Carroll's poem is more about whimsical nonsense rather than absurdist concepts.