Antonyms of verb soften

3 of 7 senses of soften

Sense 1
soften -- (make (images or sounds) soft or softer)
       Antonym of sharpen (Sense 5)
      => sharpen -- (make (images or sounds) sharp or sharper)

Sense 6
soften -- (make soft or softer; "This liquid will soften your laundry")
       Antonym of harden (Sense 2)
      => harden, indurate -- (make hard or harder; "The cold hardened the butter")

Sense 7
soften -- (become soft or softer; "The bread will soften if you pour some liquid on it")
       Antonym of harden (Sense 1)
      => harden, indurate -- (become hard or harder; "The wax hardened")

Synonyms/Hypernyms (Ordered by Estimated Frequency) of verb soften

7 senses of soften

Sense 1
soften -- (make (images or sounds) soft or softer)
       => change intensity -- (increase or decrease in intensity)

Sense 2
dampen, damp, soften, weaken, break -- (lessen in force or effect; "soften a shock"; "break a fall")
       => deaden, blunt -- (make less lively, intense, or vigorous; impair in vigor, force, activity, or sensation; "Terror blunted her feelings"; "deaden a sound")

Sense 3
yield, relent, soften -- (give in, as to influence or pressure)

Sense 4
cushion, buffer, soften -- (protect from impact; "cushion the blow")
       => modify -- (make less severe or harsh or extreme; "please modify this letter to make it more polite"; "he modified his views on same-gender marriage")

Sense 5
mince, soften, moderate -- (make less severe or harsh; "He moderated his tone when the students burst out in tears")
       => change, alter, modify -- (cause to change; make different; cause a transformation; "The advent of the automobile may have altered the growth pattern of the city"; "The discussion has changed my thinking about the issue")

Sense 6
soften -- (make soft or softer; "This liquid will soften your laundry")
       => change, alter, modify -- (cause to change; make different; cause a transformation; "The advent of the automobile may have altered the growth pattern of the city"; "The discussion has changed my thinking about the issue")

Sense 7
soften -- (become soft or softer; "The bread will soften if you pour some liquid on it")
       => change -- (undergo a change; become different in essence; losing one's or its original nature; "She changed completely as she grew older"; "The weather changed last night")

Antonyms of adj softened

2 senses of softened

Sense 1
softened -- (toned down)

INDIRECT (VIA modulated) -> unmodulated -- (characterized by lack of variation in pitch, tone, or volume; "he lectured in an unmodulated voice edged with hysteria")

Sense 2
dull, muffled, muted, softened -- (being or made softer or less loud or clear; "the dull boom of distant breaking waves"; "muffled drums"; "the muffled noises of the street"; "muted trumpets")

INDIRECT (VIA soft) -> loud -- (characterized by or producing sound of great volume or intensity; "a group of loud children"; "loud thunder"; "her voice was too loud"; "loud trombones")

Similarity of adj softened

2 senses of softened

Sense 1
softened -- (toned down)
       => modulated (vs. unmodulated) -- (changed or adjusted in pitch, tone, or volume)

Sense 2
dull, muffled, muted, softened -- (being or made softer or less loud or clear; "the dull boom of distant breaking waves"; "muffled drums"; "the muffled noises of the street"; "muted trumpets")
       => soft (vs. loud) -- ((of sound) relatively low in volume; "soft voices"; "soft music")