nesimțit

Etymology
From.

Adjective

 * 1) callous, unfeeling, inconsiderate, insensitive, uncivil, impolite

Noun

 * 1)  asshole, douchebag; someone who behaves in an inconsiderate or offensive manner

Adverb

 * 1) inconsiderately, insensitively, or callously
 * 2) stealthily (not being perceived or detected)