The state of being related, especially by kinship.(noun)
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Use "relatedness" in a sentence
"Recovery Option: Balanced relatedness is neither a withdrawal from another person nor a fusion with them."
"Jobling says that he toyed with the idea of investigating this group to see if their degree of relatedness is lower."
"I can take a car, a little red wagon, and a lawnmower, posit 'relatedness' based on similarities, arrange them in a 'progression' and theorize that one descended from the other – all with no need to mention a mechanism that brings about said changes."