speaking in a gruff manner or making something sound gruff; the act of using a rough voice or attitude.
Present participle of 'gruff' as a verb, adding -ing to show ongoing or habitual action.
The -ing form is one of English's superpowers—it lets you turn almost any verb into a noun ('gruffing' can mean the action itself), which is why '-ing' words are among the most flexible in the language.
Complete word intelligence in one call. Free tier — 50 lookups/day.