How many letters does the top answer for “a marriage song. milton.” have?

The most common answer is hymeneal (8 letters).

Crossword clue: a marriage song. milton.

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

hymeneal 8 letters web-def

a wedding hymn

hymenean 8 letters web-def

Of or pertaining to marriage; as, hymeneal rites. Pope.

a song in celebration of a marriage 50% similar → prothalamion, prothalamium