The definition of combine is to join together or to unite.
To participate in, use, enjoy, or experience jointly or in turns:
To parlay is to take something you have or something you win and transform it into something more valuable.
(Idiomatic, intransitive) To bend over at the waist.
(Nautical) To sail around:
To bring together in common cause, interest, opinion, etc.; join, as in action, through fellowship, agreement, legal bonds, etc.
Find another word for double-up. In this page you can discover 10 synonyms, antonyms, idiomatic expressions, and related words for double-up, like: combine, join, share, go-between, parlay, double-over, double, aswell, aslong and unite.