scarecrow

noun

1. an object, usually a figure of a person in old clothes, set up to frighten crows or other birds away from crops.
2. anything frightening but not really dangerous.
3. a person in ragged clothes.
4. an extremely thin person.

noun

1. an object, usually in the shape of a man, made out of sticks and old clothes to scare birds away from crops
2. a person or thing that appears frightening but is not actually harmful
3. informal
   1. an untidy-looking person
   2. a very thin person

n.1550s, from scare (v.) + crow (n.). Earliest reference is to a person employed to scare birds. Meaning “device of straw and cloth in grotesque resemblance of a man, set up in a grain field or garden to frighten crows,” is implied by 1580s; hence “gaunt, ridiculous person” (1590s). The older name for such a thing was shewel. Shoy-hoy apparently is another old word for a straw-stuffed scarecrow (Cobbett began using it as a political insult in 1819 and others picked it up; OED defines it as “one who scares away birds from a sown field,” and says it is imitative of their cry).