informal
in.for.mal \(')in-'fo.r-m*l\ \.in-(.)fo.r-'mal-*t-e-, -f*r-\
\(')in-'fo.r-m*-le-\ aj 1: conducted or carried out without formality or
ceremony 2: characteristic of or appropriate to ordinary, casual, or
familiar use - in.for.mal.i.ty n
Webster's English Dictionary