na-adjective
external; superficial; outward
Describes something that is on the surface or outward appearance, often contrasting with inner reality. Used for appearances, impressions, or external factors.
彼の態度は外面的には落ち着いているように見える。
His attitude appears calm on the surface.
外面的な変化よりも内面的な成長が大切だ。
Inner growth is more important than outward change.
表面的 also means 'superficial' or 'surface-level', but is more common and often carries a negative nuance of shallowness, whereas 外面的 is more neutral and simply contrasts with inner aspects.
Compound of 外面 (がいめん, 'external surface') + 的 (てき, '-like, -al'). The word follows a common pattern of forming adjectival nouns from nouns with 的.