conjunction
not (that), but rather; without
Used to contrast two alternatives, often in the pattern AじゃなしにB, meaning 'not A but B' or 'B rather than A'. Can also mean 'without' in some contexts. Similar to ではなく, but more colloquial.
See also: ではなしに
彼は医者じゃなしに、看護師だ。
He's not a doctor, but a nurse.
文句じゃなしに、手伝ってくれ。
Instead of complaining, help me out.