2 syllables:
aero, aero-, arrow, barrow, bero, berro, cerro, cheiro, cheiro-, chero, clairo, clero, cuero, darrow, derro, derrow, eroh, faeroe, faro, fero, ferro, ferro-, fuero, garo, garrow, gero, gero-, gerow, guero, guerro, herro, lerro, marrow, mero, meroe, merow, merowe, merrow, narrow, pairo, pharao, pharaoh, pharoah, phero, ptero, quero, serro, shero, sherrow, sparrow, spero, sphaero, sphero, stero, taro, terro, thero, varo, vero

3 syllables:
acero, aguero, albero, alero, alghero, alvero, amero, antero, antero-, armero, aspero, austero, aveiro, barbero, barquero, barreiro, bolero, bone marrow, borrero, botero, bracero, brasero, bucchero, cabrero, cajero, caldero, calero, camaro, camero, cantero, carneiro, carnero, carreiro, carrero, cartero, casero, cepero, cordeiro, cordero, course hero, crucero, cruzeiro, dattero, delnero, dinero, dinheiro, dondero, enero, entero, estero, esthero, exxaro, favero, febrero, ferreiro, ferrero, fichero, field sparrow, fisherrow, galero, gambero, gastero, gippsaero, granero, granjero, guerreiro, guerrero, handbarrow, hedge sparrow, herero, herrero, house sparrow, hystero, hystero-, ibero, ibero-, ictero, impero, intero, iraero, janiero, jezero, juazeiro, juicero, korero, latero, latero-, leggero, libero, ligero, llanero, lonero, lonkero, loureiro, lucero, madero, marero, marrero, maspero, melero, minero, mistero, monero, monteiro, montero, nispero, nonhero, nonzero, numero, omero, oneiro, otero, overo, pajero, palmero, pandeiro, passero, peguero, pepero, pierce-arrow, piffero, pineiro, pinero, pinheiro, polperro, pombero, portero, postero, potrero, primero, prospero, protero, protero-, puchero, puntero, quintero, ranchero, red sparrow, rezero, ribeiro, rivero, ropero, rosero, ruggero, salero, salgueiro, salguero, santero, sendero, sidero, silguero, sincero, soltero, sombrero, somero, song sparrow, straight-arrow, suadero, supaero, suwarrow, swamp sparrow, tablero, tenero, tercero, torero, transaero, trasero, tree sparrow, true sparrow, tubero, uparrow, valero, vaquero, velero, vimeiro, vivero, wheelbarrow, zanjero, zotero, zucchero, zurcaroh

4 syllables:
aguacero, agujero, alfarero, alfiero, anti-hero, archivero, asadero, astillero, bandolero, brasileiro, brigadeiro, burladero, caballero, cafiero, calimero, calogero, camarero, campanero, candelero, canserbero, cape passero, carbonero, carnicero, carpintero, cavalero, cavallero, cenicero, chipping sparrow, ciminero, cimitero, cocinero, colmenero, comanchero, companero, curandero, delfavero, diablero, english sparrow, escudero, espartero, extranjero, fevereiro, forastero, franco nero, ganadero, giant taro, golden yarrow, guerrillero, habanero, heredero, hormiguero, ingeniero, jardinero, java sparrow, locicero, marinero, mazzaferro, mensajero, mescalero, messaggero, messeghero, mogavero, monastero, mugavero, nakasero, new world sparrow, novillero, olivero, panadero, paradero, paterero, patintero, pederero, peluquero, peterero, pistolero, pseudo-nero, raniero, recupero, rent-a-hero, ronan farrow, saladero, salinero, straight and narrow, straniero, taliaferro, tapadero, terutero, tinajero, tyler herro, varadero, verdadero, verdulero, vesper sparrow, zapatero, zifferero

5 syllables:
atascadero, azucarero, banderillero, botafumeiro, carabinero, condottiero, eddie guerrero, elicottero, embarcadero, encomendero, financiero, frigorifero, invernadero, lillibullero, vegetable marrow, velocifero

6 syllables:
alfonso ribeiro, ana peleteiro, melissa fumero

7 syllables:
mitsubishi pajero

8 syllables:
italian vegetable marrow, rafael caro quintero, the rising of the shield hero

2 syllables:
yarrow, farrow, bureau, gyro, sorrow, zero, claro, thorough, spiro, burro, morrow, miro, burrow, euro, biro, borrow, furrow, cairo, borough, hero, harrow, beroe, pirro

3 syllables:
guacharo, sapporo, straight arrow, disk harrow, tomorrow, saguaro, broad arrow, deniro, disc harrow, ferraro, janeiro, mindoro, restharrow, sahuaro, shapiro, sokoro

4 syllables:
autogyro, autogiro, service bureau, weather bureau, pocket borough, bow and arrow, rotten borough, credit bureau, aleph-zero, antihero, bodo-garo, census bureau, poroporo, rabbit burrow

5 syllables:
kilimanjaro, absolute zero, chiaroscuro

6 syllables:
rio de janeiro, mount kilimanjaro