continuous and profound contemplation or musing on a subject or series of subjects of a deep or abstruse nature; "the habit of meditation is the basis for all real knowledge"
(religion) contemplation of spiritual matters (usually on religious or philosophical subjects)
affected by a disorder of the mind; "a mental patient"; "mental illness"
involving the mind or an intellectual process; "mental images of happy times"; "mental calculations"; "in a terrible mental state"; "mental suffering"; "free from mental defects"
of or relating to the chin- or liplike structure in insects and certain mollusks
of or relating to the mind; "mental powers"; "mental development"; "mental hygiene"
a hypothesis that has been formed by speculating or conjecturing (usually with little hard evidence); "speculations about the outcome of the election"; "he dismissed it as mere conjecture"
an investment that is very risky but could yield great profits; "he knew the stock was a speculation when he bought it"
(chemistry) a process in which one substance permeates another; a fluid permeates or is dissolved by a liquid or solid
(physics) the process in which incident radiated energy is retained without reflection or transmission on passing through a medium; "the absorption of photons by atoms or molecules"