single; only one; alone; solitary

unique; special; distinctive

dictatorial; arbitrary; acting on one's own authority

only; merely; just; specifically when highlighting an exception

(bound form) old people without children; someone who is alone and has no one to rely on

(colloquial) difficult to get along with; preferring to be alone and unwilling to socialize

a Chinese surname

unexpectedly; why; how come (used in rhetorical questions to express surprise or emphasize a situation)