^^Grafema, fonema, glifo, suono.

grapheme grafema: the smallest abstract unit of meaning that distinguishes one word from another in a writing system.
Any grapheme has many possible glyph expressions.
glyph glifo: one of the many possible grapheme expressions, all recognized as the same grapheme (by those who know that writing system).
phoneme fonema: the smallest abstract unit of sound that distinguishes one word from another in a particular language.
Any phoneme has many possible sound expressions.
sound suono: phonetic variant of a single phoneme in that language.
minimal pair (of words): 2 words that differ (in meaning) through the contrast of a single grapheme (written language) or phoneme (spoken language)

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