3 letters:
ata

4 letters:
fata, hata, lata, mata, nata, tata

5 letters:
adata, agata, alata, amata, anata, arata, botta, cdata, chata, cotta, csata, d.f.a, d.n.a, datta, dnata, elata, esata, fatah, fiata, gatta, gdata, gotta, got a, grata, guata, idata, irata, iwata, khata, kotta, lotta, miata, motta, msata, not a, ogata, omata, opata, orata, ovata, piata, plata, potta, prata, quata, riata, rotta, scata, shote, sot a, suata, ta-ta, totta, usata, vrata, wmata, yatta, zlata

6 letters:
adnata, albata, algata, anatta, aratta, arcata, armata, aurata, axiata, barata, batata, bemata, bogata, calata, cerata, chahta, codata, croate, dagata, devata, dolata, donata, emrata, encata, errata, favata, fidata, flauta, flotta, galata, hakata, hatata, hinata, hirata, incata, indata, irdata, janata, jugata, jurata, kalata, kolata, kujata, lafata, latata, licata, lobata, lopata, lunata, lyrata, maatta, malata, manata, matata, miyata, mulata, murata, nagata, nakata, napata, nowata, oughta, parata, patata, pedata, pinata, pirata, plot a, rakata, reatta, regata, renata, renate, risata, robata, sabata, sakata, salata, shot a, slot a, socata, somata, sonata, sorata, sovata, sowata, spot a, sumata, takata, tarata, tauto-, tegata, terata, thatta, umtata, vinata, virata, vyatta, yahata, yawata, yazata, yotta-, yukata, zapata, zenata

7 letters:
agliata, anahata, azafata, ballata, baratta, bharata, bingata, biodata, borgata, burrata, cannata, cantata, cascata, cassata, caudata, ciliata, clavata, corbata, cordata, covatta, dinhata, dupatta, ephrata, falcata, fellata, fregata, gaumata, gaviota, granata, gravata, gymkata, harmata, hintata, ingrata, inkatha, juniata, kenyata, kolkata, kuakata, malkata, marotta, mendota, misrata, mocatta, netdata, niigata, obovata, odonata, odorata, passata, piccata, pinnata, primata, prolata, prorata, radiata, regatta, serrata, shibata, sinuata, striata, sulcata, sunyata, thecata, toccata, trijata, trovata, ulonata, unidata, valvata, vanatta, venkata, virgata, vulgata, waratah, xstrata, zuntata

8 letters:
achelata, airavata, al-fatah, allegata, alma-ata, alouatta, anecdata, annulata, athecata, bought a, camarata, cambiata, camelote, camerata, candiote, caponata, carlotta, catarata, caught a, ciabatta, copelata, craniata, cravatta, cristata, crostata, cypriote, digitata, edentata, emerdata, ephratah, facciata, farinata, fought a, frittata, gerulata, giornata, glossata, hirakata, horchata, insalata, jannotta, judicata, kalamata, kawabata, kenyatta, labiatae, la plata, limonata, lipomata, loksatta, loricata, macerata, mahratta, manciata, matamata, metadata, minamata, naginata, nekomata, nevicata, nunziata, occhiata, oedemata, onnagata, parijata, plumbata, pro-rata, prostata, rumchata, samatata, samosata, sasumata, scarlata, serenata, shunyata, sought a, squamata, stigmata, suricata, taeniata, tanabata, taught a, teradata, traviata, uncinata, undulata, ungulata, vagbhata, vannatta, vidhaata, viewdata, wikidata, yamagata, zenyatta, zygomata

9 letters:
adenomata, aggregata, alpargata, alveolata, anawrahta, angiomata, annellata, aranciata, argonauta, aryabhata, avannaata, bangamata, bhagavata, brachiata, brought a, cabalgata, cammarata, cephalata, charulata, chipolata, cingulata, coelomata, consolata, coushatta, deciduata, devadatta, dicyemata, empyemata, fimbriata, fortunata, fulgurata, gaalipata, garrapata, gogoplata, gremolata, imbricata, imbrocata, inamorata, juan mata, koversada, laevigata, marginata, mata-mata, melismata, microdata, neuromata, oblongata, paramatta, plegepoda, prosomata, pulmonata, santagata, scotomata, siphonata, substrata, thought a, thymomata, tushratta, ultra-ata, urocerata, variegata

10 letters:
abbreviata, adjudicata, ambasciata, annunciata, annunziata, asiphonata, astronauta, astronaute, atheromata, barghawata, basilicata, bhagadatta, blastemata, capreolata, chloasmata, cioccolata, clitellata, colobomata, decacerata, dekatriata, desiderata, dinocerata, fastigiata, hanayamata, imbroccata, innominata, kuladevata, lemniscata, lysistrata, magarpatta, mahabarata, marmellata, myocommata, octocerata, oodnadatta, parramatta, perikymata, perisomata, poriferata, rawatbhata, siphoniata, skandamata, sterigmata, syntagmata, tessellata, trifoliata, vesiculata, wangaratta

11 letters:
abranchiata, aerogaviota, awgthtgtata, bambocciata, barracouata, chelicerata, cholpon-ata, coolangatta, derotremata, ferungulata, granulomata, haustellata, inconsolata, leiomyomata, mahabharata, mandibulata, monotremata, passeggiata, phantasmata, pleocyemata, ratamahatta, soppressata, superstrata, t-14 armata, tentaculata, terra cotta, testudinata, treponemata, yucca elata

12 letters:
adenomyomata, appassionata, arthropomata, chromonemata, chuquicamata, coelenterata, dibranchiata, hemangiomata, hemichordata, heterosomata, megaloblatta, megumi ogata, meningiomata, notoungulata, paenungulata, piano sonata, preoblongata, prophragmata, takeminakata, taramasalata, taramosalata

13 letters:
appendiculata, astrocytomata, echinodermata, j. r. d. tata, persona grata, plasmodesmata, postoblongata, rhabdomyomata, vishakhadatta

14 letters:
meridiungulata, notobranchiata, nudibranchiata, prosopulmonata, ryota yamagata

15 letters:
cephalochordata, cirrobranchiata, dermobranchiata, dorsibranchiata, gymnophthalmata, hydrobranchiata, mahendraparvata, pellibranchiata, prosobranchiata, prothyalosomata, pulmobranchiata, rio de la plata, scutibranchiata, tectibranchiata, tetrabranchiata, zeugobranchiata

16 letters:
capitibranchiata, cryptobranchiata, dendrobranchiata, inferobranchiata, nucleobranchiata, palliobranchiata, rayderley zapata, tubulibranchiata

17 letters:
lamellibranchiata, opisthobranchiata, pectinibranchiata, perennibranchiata, persona non grata, pulmonibranchiata, siphonobranchiata, steganophthalmata

18 letters:
pheochromocytomata

19 letters:
muscivora-forficata, sarkaru vaari paata

4 letters:
baba, gaba, gaga, nada, paca, papa, saba, saga

5 letters:
adapa, akaba, aqaba, bhaga, cauda, chaga, dhaka, draba, joppa, kokka, osaka, sabah

6 letters:
armada, badaga, calaba, casaba, gadaba, lusaka, macaca, maraca, pataca

7 letters:
pergola, formula, atakapa, granada, grenada, jellaba, kannada, kichaga, matoaka, orizaba, tostada

8 letters:
vertebra, yarmulke, ali baba, attacapa, hunkpapa, intifada, moussaka, pinctada, rum baba

9 letters:
hyperbola, orchestra, enchilada, muscicapa, nucifraga, portulaca, saxifraga, setophaga

10 letters:
proserpina, autostrada, chachalaca, crotophaga, jaboticaba, mallophaga, notostraca, tardigrada

11 letters:
addis ababa, trichophaga

12 letters:
echidnophaga, entomostraca, malacostraca

13 letters:
gulf of aqaba, mountain paca, sierra nevada

14 letters:
chondrosarcoma, spanish armada

16 letters:
chemical formula

17 letters:
molecular formula, cervical vertebra, chamber orchestra, empirical formula, capital of nevada, invincible armada

18 letters:
structural formula, symphony orchestra