English to Spanish Art/Literary Education / Pedagogy

¿Qué significa tenured en el siguiente contexto?
Many adjuncts teach at multiple universities, commuting between two or three schools in order to make ends meet, and are often unable to pursue their own academic or artistic work because of their schedules. In the past four decades, tenured and tenure-track positions have plummeted and adjunct instructor jobs have soared, second only in growth to administrators.
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