Both Uses

loathe
in
The Adventure of the Speckled Band
(Auto-generated)

I could, however, see that his face was deadly pale and filled with horror and loathing.†

loathing = disgust or intense dislike
In an instant his strange headgear began to move, and there reared itself from among his hair the squat diamond-shaped head and puffed neck of a loathsome serpent.
*

loathsome = disgusting or very bad

Definitions:

(1) (loathe)
hate, detest, or intensely dislike

Word Confusion: Do not confuse loathe with loath which sounds very similar or the same. Loathe is a verb while loath is an adjective describing "reluctance or unwillingness to do something." Note that loathing and loathsome are forms of the verb loathe even though both word forms lack the "e". Occasionally, you will see loath spelled as loathe even in a published book, but it is rare enough that it is generally considered an error rather than a non-standard spelling.
(2) (meaning too rare to warrant focus)