Antonyms of adj thrillful

1 sense of thrillful

Sense 1
thrillful -- (full of excitement; thrilled)

INDIRECT (VIA excited) -> unexcited -- (not excited; "made an unexcited appraisal of the situation")

Similarity of adj thrillful

1 sense of thrillful

Sense 1
thrillful -- (full of excitement; thrilled)
       => excited (vs. unexcited) -- (in an aroused state)