harshly uninviting or formidable in manner or appearance; "a dour, self-sacrificing life"; "a forbidding scowl"; "a grim man loving duty more than humanity"; "undoubtedly the grimmest part of him was his iron claw"- J.M.Barrie
direct carefully and safely; "He navigated his way to the altar"
act as the navigator in a car, plane, or vessel and plan, direct, plot the path and position of the conveyance; "Is anyone volunteering to navigate during the trip?"; "Who was navigating the ship during the accident?"
an impenetrable barrier to communication or information especially as imposed by rigid censorship and secrecy; used by Winston Churchill in 1946 to describe the demarcation between democratic and communist countries
the position of greatest importance or advancement; the leading position in any movement or field; "the Cotswolds were once at the forefront of woollen manufacturing in England"; "the idea of motion was always to the forefront of his mind and central to his philosophy"