the word 'unselfishly' is a modern english formation built upon the core germanic noun 'self,' which traces back to proto-germanic selbaz. the negative prefix 'un,' also of ancient germanic lineage, is attached to the adjective 'selfish,' which itself is derived from 'self' with the adjectival suffix '-ish,' meaning "characteristic of." the final adverbial suffix '-ly' then modifies the adjective into a manner of action. thus, the literal construction "in the manner of not being characteristic of one's own self" elegantly captures the modern abstract meaning of acting with concern for others. this compound word exemplifies the analytic and combinatory power of english, layering affixes onto a core concept to precisely articulate a specific quality of behavior.

Structure: un (not) + self (own person) + ishly (in the manner of) - un: a prefix of germanic origin, meaning "not," used to give a negative or opposite force. - self: a noun of old english origin, from proto-germanic, meaning "one's own person." - ishly: a compound suffix formed from '-ish' (an adjective suffix of old english origin, meaning "having the character of") and '-ly' (an adverb-forming suffix of old english origin, meaning "in a manner").