How many letters does the top answer for “line of descent traced through the paternal side of the family” have?

The most common answer is agnation (8 letters).

Crossword clue: line of descent traced through the paternal side of the family

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

agnation 8 letters wn-def

line of descent traced through the paternal side of the family

patrilineage 12 letters wn-def

line of descent traced through the paternal side of the family