Ma'anar ƙamus na kalmar "adsorb" ita ce tara ko tara kwayoyin halitta, atom, ko barbashi na wani abu a saman wani abu mai ƙarfi ko ruwa ta hanyar mannewa, ba tare da fuskantar wani sinadari ba. Abun da aka tallatawa yana manne da saman kayan kuma ana gudanar da shi ta wurin dakiyoyi masu ban sha'awa kamar Van der Waals, haɗin gwiwar hydrogen, ko hulɗar lantarki. Tsarin adsorption ya bambanta da sha, wanda wani abu ke narkar da shi ko kuma ya shiga cikin mafi girman wani abu.