insignis

Insignis, insigne is a third declension adjective of two terminations: one form for masculine and feminine, a separate neuter in -e. The ablative singular is insigni, not insigne, which is the regular i-stem pattern.

It is built from in plus signum, so the literal sense is "marked out", and the neuter noun insigne, insignis means the mark itself: a badge, an emblem, and in the plural insignia, the regalia of office. English took that plural whole. The adjective is neutral about which way you stand out, but it leans complimentary; for conspicuous in a bad way Latin usually reaches for notus with a sour word attached, or simply for infamis.