Synonyms for Mediocre (same or very similar meaning)
WordNet sense 1 (moderate to inferior in quality):
second-rate
WordNet sense 2 (of low or inferior quality):
inferior
WordNet sense 3 (lacking exceptional quality or ability):
average, fair, middling
WordNet sense 4 (not exceptional in any way especially in quality or ability or size or degree):
ordinary
WordNet sense 5 (having undesirable or negative qualities):
bad
From the ODE community, based on WordNet
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