What is the meaning of Sound-symbolic?

characterized by sound symbolism

  1. (of a unit of sound or meaning such as a word, morpheme, phoneme, syllable, etc.) composed of speech sounds that are not arbitrary but also not overtly onomatopoeic

    (of a unit of sound or meaning such as a word, morpheme, phoneme, syllable, etc.) composed of speech sounds that are not arbitrary but also not overtly onomatopoeic

    Source: wiktionary.org