Webster's Revised Unabridged Dictionary · 1913

Disloyal

Disloyal , adjective

[Prefix dis- + loyal: compare Old French desloial, desleal, French déloyal. See Loyal.]

Not loyal; not true to a sovereign or lawful superior, or to the government under which one lives; false where allegiance is due; faithless; as, a subject disloyal to the king; a husband disloyal to his wife.
Without a thought disloyal. — Mrs. Browning