MILT Meaning of MILT in English noun the spermatic fluid of fishes. 2. milt ·noun the spleen. 3. milt ·vt to impregnate (the roe of a fish) with milt. 4. milt ·noun the testes, or spermaries, of fishes when filled with spermatozoa. Webster English vocab. Английский словарь Webster. 2012