1) Digit 2) Figure 3) Four 4) Foursome 5) Little joe 6) Quartet 7) Quatern 8) Quaternary 9) Quaternion 10) Quaternity 11) Tetrad 1) Four 2) Quartet 3) Quatern 4) Quaternion 5) Quaternity 6) Tetrad 
a four-syllable foot.
• (n.) A collection or combination of four of a kind. • (n.) A cycle for carrying four riders, so arranged that all the reders can assist in the propulsion. • (n.) Four children born in the same labor.
(from the article `multiple birth`) ...one of which divided to produce MZ twins while the other developed as a singleton (the three constituting DZ triplets); or from three separate ...
One of four children born at one birth. ... Synonym: quadrigeminus. ... Origin: L. Quadruplus, four fold ... (05 Mar 2000) ... 
(kwod-rldbomacp´lәt) one of four offspring produced at one birth.
A four-syllable foot.
Quad'ru·plet noun [ From Quadruple .] 1. A collection or combination of four of a kind. 2. pl . Four children born in the same labor. 3. A cycle for carrying four riders, so arranged that all the reders can assist in the propulsion. 
Type: Term Pronunciation: kwah-drup′let Definitions: 1. One of four children born at one birth. Synonyms: quadrigeminus
Four children born at the same time from the same pregnancy . Although identical quadruplets are rare, it is possible for the pregnancy to produce two sets of identical twins, one set of identical twins and two fraternal babies, all identical or all fraternal.
[n] - one of four children born at the same time from the same pregnancy
quadruple noun a set of four similar things considered as a unitquad noun one of four children born at the same time from the same pregnancy
any group or combination of four. · four children or offspring born of one pregnancy. · one of four such children or offspring. · a group of four notes of equal value performed in the time normally taken for three.