noun
person of great renown; prominent figure
Refers to a person widely respected and influential, often in a community or field. Slightly formal and somewhat literary.
彼は地元の名望家として知られている。
He is known as a prominent figure in the local community.
その会合には多くの名望家が出席した。
Many persons of great renown attended the meeting.
有名人 simply means 'celebrity' or 'famous person', without the nuance of deep respect or community standing that 名望家 carries.
Compound of 名望 (めいぼう, 'fame and popularity') + 家 (か, 'person'). The exact historical derivation is uncertain, but the word follows a common pattern for describing a person of a certain quality.