Brahmā (ब्रह्मा) who is the creator aspect of the Trimurti God, while Vishnu (विष्णु) and Shiva (शिव ) being the Preserver and the Destroyer aspects.
The most frequently used etymological meaning for Vishnu and Shiva which I have encountered almost everywhere is :-
Vishnu (विष्णु) = The all pervader, who is everywhere, all pervading. The One who enters (everywhere?), etc.
Shiva (शिव ) = The all auspicious one, the one who's Pure and the most auspicious, etc.
For the word Brahmā (ब्रह्मा), I haven't found anywhere, any proper etymology and meaning.
I'd like to know (with scriptural as well as non-scriptural references too) all possible etymology and meanings of all of the Trimurtis - Brahmā, Vishnu, Shiva, with specific emphasis on Brahmā (ब्रह्मा).