No, not even in French, where there are Infinitives that end in -IR and -ER, but not in -AR.
Generally, words that end in -ar -er and -ir are the infinitive forms of verbs, e.g. to be, to run, to jump, to talk, etc.
Perhaps other Spanish words that end with -ar. cantar
I don't think there is one, unless you stretch the rhyme a lot. The end of the word "ornaments" kind of rhymes with parents, but not fully. "ments" and "rents" rhyme, but "na" and "ar" don't, even though they both have an a. Presents is similar... the end rhymes, but not the rest of the word.
Some words that can be formed with AR:ArcadeArchaicArcherArcheryArchArchiveArcticArdentArdorAreAren'tArgonArgotArgyleArmorArmageddonArmArmyArrangeArrangementArrayArrhythmiaArrestArrowArsenalArsonArteryArthritisArtichokeArticleArticulateArtificialArtistArtsyArtSome words that have AR in them:AlarmBareBarCareCarpetCarCartCharmCharChartDareDartDearthEarnEarEarthFareFarmFarFearGarGearHareHarmHartHearHeartJargonJarLargeLarkLearnMarchMareMarginalMargeMarkMarrowNarcNarrowNearOarParePartPartyPearQuarterQuartetQuartRareRearShareSpareStareTareTarpTearVariantVarietyWareWearYardYarnYear
or is usually masculine mostly used in profession ir usually indicates that verb is in third category ar usually indicates that verb is in first category
That's a vanity card by Chuck Lorre:http://chucklorre.com/index.php