naphthaleneacetic acid

noun

naph·​tha·​lene·​acetic acid

: either of two crystalline naphthyl derivatives C₁₀H₇CH₂COOH of acetic acid

especially : the alpha or 1-compound used as a growth regulator for plants (as for preventing drop of apples before normal harvest time)

Word History

Etymology

naphthalene + acetic

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