the.com/head of state

means The person who formally embodies and represents a country — the ceremonial or constitutional top of the national org chart, whether or not they actually run the government day to day.

from Simple compound sense, not exotic etymology: 'head' carrying its old metaphorical weight — the ruling or topmost part of a body, as in 'head of a household' or 'head of a table' — tracing back through Old English 'heafod' to the literal skull-and-brains sense, with 'top of the body' becoming 'top of the hierarchy' long before anyone used it for nations. 'State' comes from Latin 'status' ('condition, standing'), which narrowed over centuries into 'the organized political community' — the sense cemented in phrases like 'affairs of state.' Bolt them together and you get a straightforward 18th/19th-century political phrase: the figurehead atop the body politic, distinct from the 'head of government' who actually does the governing.