From ⵜⴰⴳⴷⴰ (tagda, “equation”) + ⴰⵣⴰⵍ (azal, “value”) + ⵜ- -ⵜ (t- -t), literally “same values”.
ⵜⴰⴳⴷⴰⵣⴰⵍⵜ • (tagdazalt) f