ingratiatory comes from ingratiate (from Latin phrase in gratiam, 'into favor', from gratia 'favor, grace') + the adjective suffix -ory. Latin gratia derives from gratus ('pleasing'). Morphologically, the ending is part of the etymology: the suffix is attached to the older base named in the history, producing a later English derivative. In present English, the adjective sense is "intended to win favor or approval; ingratiating", so the historical development ends in a clearly identifiable modern dictionary use. The same base also appears in related forms such as ingratiate, ingratiation, grace, and gracious. Its semantic neighborhood includes ingratiating, fawning, obsequious, and flattering, which helps locate the modern sense without adding a separate etymological claim. The named historical forms include Latin in gratiam, Latin gratia, and Latin gratus.