(adverb) mutually; each other; typically used before verbs or in four-character patterns

Negative adverb used before verbs, adjectives, and other adverbs to indicate negation; also used as a bound-form prefix to form terms with opposite meanings

to invade or intrude upon a territory; to violate another country's border by force

A formal agreement between countries or international organizations regarding rights and obligations in areas such as politics, economy, military, or culture; pact