Synonyms and related words :
Pastoral Epistle, aerogram, aimlessness, air letter, airgraph, billet-doux, bull, chain letter, dimissorial, dimissory letter, drop letter, emptiness, empty sound, encyclical, fan letter, form letter, futility, inanity, insignificance, letter of credit, letter of introduction, letters credential, letters of marque, letters of request, letters overt, letters patent, letters rogatory, love letter, meaninglessness, mere noise, monitory, newsletter, nixie, noise, nonsensicality, nullity, open letter, pastoral letter, phatic communion, poison-pen letter, purposelessness, round robin, senselessness, unmeaningness, unsignificancy