Seven - Vine's Expository Dictionary of New Testament Words
Seven[ 1,,G2033, hepta ]
whence Eng. words beginning with hept," corresponds to the Heb. sheba' (which is akin to saba', signifying "to be full, abundant"), sometimes used as an expression of fullness, e.g., Ruth 4:15, it generally expresses completeness, and is used most frequently in the Apocalypse; it is not found in the Gospel of John, nor between the Acts and the Apocalypse, except in Hebrews 11:30 (in Romans 11:4 the numeral is heptakischilioi, "seven thousand"); in Matthew 22:26 it is translated "seventh" (marg., "seven").
Note: In 2 Peter 2:5, RV, "Noah with seven others" is a translation into idiomatic English of the Greek idiom "Noah the eighth person" (so AV, translating literally). See EIGHT.