SELFLESSLY
altruistically, selflessly
(adverb) in an altruistic manner; “he acted selflessly when he helped the old lady in distress”
Source: WordNet® 3.1
Etymology
Adverb
selflessly (comparative more selflessly, superlative most selflessly)
In a selfless manner; done in a way that disregards concerns for the self and places other first.
Source: Wiktionary
SELFLESS
Self"less, a.
Definition: Having no regard to self; unselfish.
Lo now, what hearts have men! they never mount As high as woman in
her selfless mood. Tennyson.
Source: Webster’s Unabridged Dictionary 1913 Edition