You searched for: “ducked
ducked, duct
ducked (DUK't) (verb)
To lower the head or body quickly; especially, so as to avoid something; to dodge or to evade: "The people ducked so they wouldn't hit their heads on the lower than normal door frames."
duct (DUKT) (noun)
1. A tubular passage through which a substance; especially, a fluid, is conveyed: "The roofer installed a new rain duct along the edge of the roof."
2. A bodily passage, particularly one for secretion: "The duct from the kidney was blocked and it was very painful for the patient."

When Stan walked in the basement, he ducked his head so he wouldn't hit it on the heating duct coming from the furnace.