cousin

Etymology

From Middle English cosyn, from Old French cosin, from Latin cōnsōbrīnus (possibly via a Vulgar Latin form *cōsōbīnus > *cōsuīnus), from com- + sōbrīnus.

noun

1. The child of a person's uncle or aunt; a first cousin.
   I think my cousin is a good man.
2. (archaic) A kinsman.
3. Any relation who is not a direct ancestor or descendant but part of one's extended family; one more distantly related than an uncle, aunt, granduncle, grandaunt, nephew, niece, grandnephew, grandniece, etc.
4. (obsolete) A title formerly given by a king to a nobleman, particularly to those of the council. In English writs, etc., issued by the crown, it signifies any earl.
5. (figurative) Something kindred or related to something else.
   Partnering, along with its less irritating cousin "partnership", crops up all over the place, being equally useful to the lazy jargoneer and the lazy policy-maker. It has been said that there is no noun which cannot be verbed; in the same way, there is now nothing, concrete or abstract, which cannot be partnered. Nov 21 2003, Tim Homfray, “What do they mean...”, in Times Educational Supplement, UK, retrieved 2012-11-20
   NASA has discovered an Earth-like planet orbiting around a star, which a NASA researcher called a “bigger, older cousin to Earth.” July 23 2015, Tessa Berenson, “NASA Discovers New Earth-Like Planet”, in Time
6. (espionage, slang, chiefly in the plural) A member of the British intelligence services (from an American perspective) or of the American intelligence services (from a British perspective).