Re*tard"er (?), n. One who, or that which, retards.

Re*tard"er (r&esl;*tär"d&etilde;r), n. 1. (Steam Boiler) Any of various devices, as a helix of flat metal strip, introduced into a boiler tube to increase the heating effect of the fire.

2. (Photog.) A substance, as potassium bromide, added to a developer to retard its action.

Re*tard"er (?), n. One who, or that which, retards.

Re*tard"er (r&esl;*tär"d&etilde;r), n. 1. (Steam Boiler) Any of various devices, as a helix of flat metal strip, introduced into a boiler tube to increase the heating effect of the fire.

2. (Photog.) A substance, as potassium bromide, added to a developer to retard its action.