Is there a unit of time bigger than Millennium that still measures years?

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According to Wikipedia (http://www.reference.com/browse/wiki/Annum) megaannum, usual symbol Ma, is a unit of time equal to one million (106) years. It is commonly used in scientific disciplines such as geology, paleontology, and celestial mechanics to signify very long time periods in the past. For example, the dinosaur species Tyrannosaurus rex was abundant approximately 65 Ma (65 million years) ago (ago may not always be mentioned; if the quantity is specified while not explicitly discussing a duration, one can assume that "ago" is implied; "mya" includes "ago" explicitly.). In astronomical applications, the year used is the Julian year of precisely 365.25 days.
  • gigaannum, usual symbol Ga, is a unit of time equal to one (short scale) billion (109) years. It is commonly used in scientific disciplines such as cosmology and geology to signify extremely long time periods in the past. For example, the formation of the Earth occurred approximately 4.57 Ga (4.57 billion years) ago.
  • exaannum, usual symbol Ea, is a unit of time equal to (1018) years (one quintillion on the short scale, one trillion on the long scale). It is an extremely long unit of time. The half-life of tungsten-180 is 1.8 Ea.
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What unit of measurement is bigger than an acre?

The hectare is 10,000 square meters. An acre is about 4,047 square meters, so there are about 2.47 acres in a hectare.. Certainly there are other units of area measure that