truancy (n.)

c. 1200, "beggar, vagabond," from Old French truant "beggar, rogue" (12c.), as an adjective, "wretched, miserable, of low caste," from Gaulish *trougant- (compare Breton *truan, later truant "vagabond," Welsh truan "wretch," Gaelic truaghan "wretched"), of uncertain origin. Compare Spanish truhan "buffoon," from same source. Meaning "one who wanders from an appointed place," especially "a child who stays away from school without leave" is first attested mid-15c.

abstract noun suffix of quality or rank, from Latin -cia, -tia, from Greek -kia, -tia, from abstract ending -ia (see -ia) + stem ending -c- or -t-. The native correspondents are -ship, -hood.