hooter comes from hoot (of imitative origin) + -er, denoting a device that hoots; the 'nose' sense is British slang. Morphologically, the ending is part of the etymology: the suffix is attached to the older base named in the history, producing a later English derivative. The etymology remains cautious where the history is cautious: comparisons, echoic formation, or disputed derivation do not make the ancestry more definite than the forms actually named. In present English, the noun sense is "a device that makes a hooting sound, such as a horn or siren", so the historical development ends in a clearly identifiable modern dictionary use. The same base also appears in related forms such as hoot. Its semantic neighborhood includes horn, siren, klaxon, and whistle, which helps locate the modern sense without adding a separate etymological claim. The named historical forms include onomatopoeic hoot.