Nazla (ar. — furud omadan), dar tibbi qadim bemoriest, ki dar natijai az qismi peshi mayna ba khalq, bini, shush, sina, meda va gayra furud omadani fuzul (moddahoi tari nodarkor) ba vujud meoyad, Masalan, ba bini rekhtani fuzulro odatan zukom menomidand. Nazla du nav meshavad: 1) Nazlai garm, ki raqiku suzishovaranda ast va az on harorati badan baland meshavad. 2) Nazlai sard, galiz yo raqiq ammo suzish na dorad, harorati badan mutadil ast. Hangomi Nazma bazan dar poyoni peshoni, dar zeri abruho va atrofi onho bemor dardi sakhtro his mekunad
Dar tibbi muosir Nazla, takhminan, guruhi kasalihoi siroyatnoki (viru- sii) rohhoi nafas (gripp, zukom, laringit, faringit, sinusitho) va oqibathoi badi onhoro ifoda menamoyad.