decade

noun

1. a period of 10 years

   noun.time

   Synonyms decennary decennium

   Source: WordNet 3.0

2. the cardinal number that is the sum of nine and one; the base of the decimal system

   noun.quantity

   Synonyms 10 ten tenner x

   Source: WordNet 3.0

3. A group or division of ten; esp., a period of ten years; a decennium; as, a <i>decade</i> of years or days; a <i>decade</i> of soldiers; the second <i>decade</i> of Livy.

   noun

   Source: webster1913