vestigial
adjective
[ vɛˈstɪdʒɪəl ]
• forming a very small remnant of something that was once greater or more noticeable.
• "he felt a vestigial flicker of anger from last night"
• (of an organ or part of the body) degenerate, rudimentary, or atrophied, having become functionless in the course of evolution.
• "the vestigial wings of kiwis are entirely hidden"
