1. A task or job that is performed infrequently or on an irregular basis, not part of regular duties
Fixing the roof is an occasional task that we only do every few years.
Reparar o telhado é uma tarefa ocasional que fazemos apenas a cada alguns anos.
2. Work undertaken from time to time as needed, rather than as a permanent or routine responsibility
She takes on occasional tasks as a freelance consultant.
Ela realiza tarefas ocasionais como consultora freelancer.