It seems a mistake for some verbal inflection, such as verbs/tillaran, verbs/hilaran, verbs/tildaran, but most likely it lacks an accent to be Tilarán (Costa Rican canton).
In Nahuatl language it means place where it rains mecho, rainy place or place of great rain.
Name received by the 8th canton of The Province of Guanacaste, Costa Rica CA