surface; face (visible side of an object) / front (of a building), obverse side of a coin ("heads") / cover attached to a surface / outer clothing / facade; appearance; outside; exterior

first, foremost, number one

front of something

appearance / expression / surface / front / exterior / outward / outwardly / outward appearance / countenance

group of people, animals, etc.

a group of people, animals, etc. / (group theory) a group

(colloquial) to be sexually turned on, to be horny

in a mottled or splotchy fashion, irregularly / in an energetic and swarming or flocking manner

crowded / group

ordinal marker, often with affix 号