Polish

Signage on Polish municipal police (Straż Miejska) cars uses both the standard form (Ż, on the door) and the variant with horizontal stroke (Ƶ, on the roof sign)

In the Polish language, ż is the final, 32nd letter of the alphabet. It typically represents the voiced retroflex fricative ([ʐ]), somewhat similar to the pronunciation of ⟨g⟩ in "mirage"; however, in a word-final position or when followed by a voiceless obstruent, it is devoiced to the voiceless retroflex fricative ([ʂ]).

Its pronunciation is the same as that of the digraph ⟨rz⟩, except that ⟨rz⟩ (unlike ⟨ż⟩) also undergoes devoicing when preceded by a voiceless obstruent. The difference in spelling comes from their historical pronunciations: ż originates from a palatalized /ɡ/ or /z/, while ⟨rz⟩ evolved from a palatalized ⟨r⟩.^[1]

The letter was originally introduced in 1513 by Stanisław Zaborowski in his book Ortographia.^[2]

Occasionally, the letter Ƶ ƶ (Z with a horizontal stroke) is used instead of Ż ż for aesthetic purposes, especially in all-caps text and handwriting.

Kashubian

Kashubian ż is a voiced fricative like in Polish, but it is postalveolar ([ʒ]) rather than retroflex.

Maltese

City limit sign of Żurrieq in Malta

In Maltese, ż represents the voiced alveolar sibilant [z], pronounced like "z" in English "maze". This contrasts with the letter ⟨z⟩, which represents the voiceless alveolar sibilant affricate [ts], like in the word "hats".