Synonyms for Slow (same or very similar meaning)
WordNet sense 1 (so lacking in interest as to cause mental weariness):
boring, dull, ho-hum, irksome, tedious, tiresome, wearisome, deadening
WordNet sense 2 (arousing no interest or attention or curiosity or excitement):
uninteresting
WordNet sense 3 ((of tempo) slow):
lento
WordNet sense 4 (with little movement; very slow):
sluggish, sulky
WordNet sense 5 (moving slowly and gently):
lazy
WordNet sense 6 (wasting time):
dilatory
WordNet sense 7 (slow to learn or understand; lacking intellectual acuity):
dense, dim, dumb, obtuse
WordNet sense 8 (lacking or marked by lack of intellectual acuity):
stupid
WordNet sense 9 (cause to proceed more slowly):
slow up
WordNet sense 10 (become slow or slower):
slack, slacken
WordNet sense 11 (lose velocity; move more slowly):
decelerate
WordNet sense 12 (of timepieces):
behind
WordNet sense 13 (without speed (`slow' is sometimes used informally for `slowly')):
easy, slowly, tardily
WordNet sense 14 (lacking activity; lying idle or unused):
inactive
From the ODE community, based on WordNet
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