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Related to retarder: surface retarder, concrete retarder

re·tard 1

v. re·tard·ed, re·tard·ing, re·tards
To cause to move or proceed slowly; delay or impede.
To be delayed.
1. A slowing down or hindering of progress; a delay.
2. Music A slackening of tempo.

[Middle English retarden, from Old French retarder, from Latin retardāre : re-, re- + tardāre, to delay (from tardus, slow).]

re·tard′er n.

re·tard 2

n. Offensive Slang
1. Used as a disparaging term for a person with an intellectual disability.
2. A person considered to be foolish or socially inept.

[Short for retarded.]


1. a person or thing that retards
2. (Chemistry) a substance added to slow down the rate of a chemical change, such as one added to cement to delay its setting
References in periodicals archive ?
If there is no vent in the vicinity, check the band joists and, if they are not fully insulated, please do so by placing R-19 fiberglass or Roxul insulation tightly against the band joists throughout the crawl space and staple a plastic vapor retarder to the floor sheathing, the sides of the joists and the mud sill in each space to protect the insulation from moisture migration.
It transfers custom or stock patterns as a surface retarder via membrane placed at the bottom of the form.
The 2015 IRC requires a Class I or Class II vapor retarder on the interior of a framed wall assembly (see Table 1 for class definitions).
La satisfaction de la demande de l'organisation ne peut retarder l'execution de toute decision administrative conformement aux conditions enoncees par l'article 81 du reglement du tribunal administratif", a-t-elle precise.
Le ministre de la Jeunesse et des Sports, El Hadi Ould Ali, a suggere, hier, comme [beaucoup moins que] mesure d'urgence [beaucoup plus grand que], de retarder la mise en œuvre de l'application du contenu de l'article 6 du decret executif 15-74 du 16 fevrier 2015, objet de contestation des clubs des sports collectifs, a indique son departement.
An optical retarder can be easily implemented by birefringent optical media such as PMF or optical waveguides on LiNbO3.
The Minetruck MT42 is ready-wired for an optional electromagnetic retarder braking system.
Saleh a ajoute dans une declaration a la SUNA que certains partis politiques ont travaille a retarder le dialogue en ne pas appeler les participants au mecanisme (7 +7) dementant que le retard de (PCN) disant que le parti est desireux de inviter toutes les parties au dialogue pour atteindre cet objectif en consideration un engagement politique.
La pluie devra aussi retarder les travaux de recolte qui sont toujours en cours.
The Generation 9 TA400 is equipped with dual retarder systems, a transmission retarder and exhaust brake, giving operators increased control in loaded, downhill hauls.
Any time humidity creeps upward of 50%, should moisture-laden air permeate the vapor retarder and insulation and come into contact with the metal roof, there is the propensity for condensation to form," Manufacturing facilities and large structures like gymnasiums are particularly vulnerable to this kind of problem.
Tokyo, Feb 15, 2013 - (JCN) - Through joint research with Professor Yasuhiro Koike of Keio University, Toyobo has developed COSMOSHINE, a polyester-based super retarder film (SRF) that uses the features of LED light sources to eliminate interference fringes (rainbow mura).