Onomastika (az yunoni onomastikds — sanati nomguzori, onoma — nom), 1) yak shubai ilmi zabonshinosiro guyand, ki tarikhi paydoish va tahavvuli ismoi khosro meomuzad; 2) majmui hama guna ismhoi khos (leksikai onomastiki), onim i ya, ki vobasta ba obekti nombarshavanda ba antroponimho (nomi ashkhos), etnonimho (nomi qavmho, millatho, khalqho), toponimho (nomi makonho), gidronimho (nomi daryoho), kosmonimho (nomi jirmhoi osmoni), teonimho (nomi ezidonu farishtaho), demonimho (nomi ofarinishi bad), zoonimho (nomi hayvonot), fitonimho (nomi rastaniho), faleronimho (nomi mukofotho, nishonho, medalho), khrematonimho (nomi ashyo, asarhoi ilmivu badei, jashnu marosimho, muassisaho, navhoi mahsulot) va gayra taqsim meshavand.
Onomastika mahsuli tafakkuri davrahoi gunoguni inkishofi jamiyat, boigarii manavi, ganjinai boetimodi tarikhu madaniyat va yak hissai muhimi fondi lugavii zabon buda, baroi tadqiqi masalahoi etimologiya, fonetika, kalimasozi, shevashinosii tarikhiyu muosir yori merasonad.
Onomastika bo mantiq, psikhologiya, etnografiya, tarikh, arkheologiya, geografiya, geologiya, numizmatika, sotsiologiya, adabiyotashnosiyu uslubshinosi aloqa dorad. Hodisa va voqeahoi gunoguni jamiyat, digargunihoi ijtimoivu madani dar sistemai Onomastika inikos meyoband. Sistemam Onomastika dar omuzishi masalahoi tarikhi urfu odat, rasmu oin, tafakkuru jahonbini, madaniyat va gayra ahamiyat dorad.
Baze sohahoi Onomastikai tojik, az jumla, masalahoi toponimiya az tarafi R. X. Dodikhudoev, S. I. Klimchitskiy, L. I. Rozova, A. V. Rozeyafeld, O. I. Smirnova, A. L. Khromov, antroponimiya az tarafi Ya. I. Kalontarov, R. O. Ortiqov, O. F. Gafurov mavridi omuzish qaror giriftaand.
Adabiyot: Dodikhudoev R. X., Pamirskaya mikrotoponimiya, Dushanbe, 1975; Rozova L. I., Slovar geograficheskikh terminov i drugikh slov, formiruyushikh toponimiyu Tadjikskoy SSR, Moskva, 1975; Khromov A. L., Ocherki po toponimii i mikrotoponimii Tadjikistana. Vipusk 1 Dushanbe, 1975; Fafurov O.. Sharhi ismu laqabho, Dushanbe, 1961.