soft ‧ en ‧ er /ˈsɒf ə nə $ ˈsɒːf ə nər/ BrE AmE noun [uncountable and countable]
[ Word Family: noun : ↑ softness , ↑ softener , SOFTIE/SOFTY ; verb : ↑ soften ; adverb : ↑ softly ; adjective : ↑ soft ]
a substance that you add to water to make clothes feel soft after washing:
fabric softener
⇨ ↑ water softener