a personal name, contains the elements "black" (tlil-), "reed" (aca-), and a reverential suffix; it could also have an -a- from water (atl) hiding in there (see attestations); the name also appears without the reverential suffix (-tzin)
A person named Pablo Tlilacatl was a member of the group that was congregated in 1559 at San Bernabé Temoztitlan near Cholula.
Another person named Tlilacatl appears in the Codex Xolotl. See the study by Charles Dibble (1996, 111) which explains: "de 'tlilli' = negro ; 'atl' = agua y 'acatl' = caña." (SW)
A doña María Tlilacatzin appears in the Techialoyan manuscript associated with Cuajimalpa. See the study of it by Ignacio Silva (2002, 20).
A person named Tlilacatl also appears in the Matrícula de Huexotzinco, folio 716 recto. https://www.loc.gov/resource/gdcwdl.wdl_15282/?sp=510&st=image&r=0.137,0... In this reference, the glyph shows a long strip of paper with what appears to be writing on it, plus a hand holding a writing implement. (SW)