Some languages contrast more than two trills phonemically

Trill consonant. https://en.wikipedia.org/wiki/Trill_consonant

and Ninde have phonemically voiceless bilabial trills. The Czech language has two contrastive alveolar trills, one a fricative trill (written ř in the In phonetics, a trill is a consonantal sound produced by vibrations between the active articulator and passive articulator. Standard Spanish ⟨rr⟩ as in perro, for example, is an alveolar trill. A trill is made by the articulator being held in place and the airstream causing it to vibrate. Usually a trill vibrates for 2–3 contacts, but may up to 5, or even more if geminate. However, trills may also [𝼀] – Velopharyngeal trill; the velopharyngeal fricative [ʩ] found in disordered speech sometimes involves trilling of the velopharyngeal port, producing a 'snort'. The bilabial trill is uncommon. The coronal trill is most frequently alveolar [r͇], but dental and postalveolar articulations [r̪] and [r̠] also occur. An alleged retroflex trill found in Toda has been transcribed [ɽ] (that is, the same as the retroflex flap), but might be less ambiguously written [ɽr], as only the onset is retroflex, with the actual trill being alveolar. The epiglottal trills are identified by the IPA as fricatives, with the trilling assumed to be allophonic. However, analyzing the sounds as trills may be more economical. There are also so-called strident vowels which are accompanied by epiglottal trill. The cells in the IPA chart for the velar, (upper) pharyngeal, and glottal places of articulation are shaded as impossible. The glottis quite readily vibrates, but this occurs as the phonation of vowels and consonants, not as a consonant of its own. Dorso-palatal and velar vibratory motions of the tongue are occasionally produced, especially during the release of dorsal stops, and ingressive velar trills occur in snoring, but not in normal speech. The upper pharyngeal tract cannot reliably produce a trill, but the epiglottis does, and epiglottal trills are pharyngeal in the broad sense. A partially devoiced uvular or pre-uvular (i.e. between velar and uvular) trill [ʀ̝̊] with some frication occurs as a coda allophone of /ʀ/ in the Limburgish dialects of Maastricht and Weert. Voiceless trills occur phonemically in e.g. Welsh and Icelandic. (See also voiceless alveolar trill, voiceless retroflex trill, voiceless uvular trill.) Mangbetu and Ninde have phonemically voiceless bilabial trills. The Czech language has two contrastive alveolar trills, one a fricative trill (written ř in the orthography). In the fricative trill the tongue is raised, so that there is audible frication during the trill, sounding a little like a simultaneous [r] and [ʐ] (or [r̥] and [ʂ] when devoiced). A symbol for this sound, [ɼ], has been dropped from the IPA, and it is now generally transcribed as a raised r,…