means The act of carefully watching or noticing something, often to gather information or draw conclusions, sometimes resulting in a remark about what you've seen.

from From Latin 'observatio,' from 'observare' — to watch over, attend to, guard. It splits into 'ob-' (toward, over) and 'servare' (to keep, watch, preserve), the same 'servare' that guards 'conserve' and 'preserve.' The word arrived in English through Old French in the late Middle Ages, first carrying a sense of keeping or heeding a rule or custom — you 'observed' the Sabbath before you ever 'observed' a sparrow.