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Webster 1913 Edition

Noun.

[St.

Martin + mass

religious service.]

(Eccl.)

The feast of

St. Martin

, the eleventh of November; – often called

martlemans

Martinmas summer

a period of calm, warm weather often experienced about the time of Martinmas; Indian summer.

Percy Smith.

Noun.

[Martin and mass.] The feast of St. Martin, the eleventh of November.

Martinmas ‎(plural Martinmases)

St. Martin's Day