(a.) Twice paired, as when a petiole forks twice.

accouple accumulate affiliate affiliated agglutinate allied amalgamated amass analyze articulate assemble assimilated associate associated band biconjugate bigeminate bijugate blended bond bound bracket bracketed bridge bridge over cement chain clap together coalesce coincident collateral collect combinative combinatory combine combined compact comprehensive comprise concatenate concurrent conglobulate conjoin conjoint conjugated conjunct conjunctive connect connected connective consolidated copulate corporate correlated couple couple up coupled cover decline derivative double-harness double-team echoic eclectic embrace encompass etymologic fused gather glue hyphenate implicated include inclusive incorporated inflect integrated interlinked interlocked interrelated involved join joined joint knot knotted lay together league lexical lexicographic lexicologic lexigraphic link linked lump together mark marry marshal mass match matched mate mated merge merged mixed mobilize of that ilk of that kind one onomastic onomatologic onomatopoeic pair pair off paired parallel parenthesize paronymic paronymous parse piece together point punctuate put together related roll into one solder span splice spliced stick together syncretistic syncretized synthesized take in tape team team up tie tied twinned unify unite united wed wedded weld yoke yoked