KEY: Observation.

SYN: Contemplation, study, remark, attention, notice, comment.

ANT: Disregard, oversight, inadvertence, inattention, silence, ignorance.

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KEY: Observe.

SYN: Remark, mark, watch, note, behold, perceive keep, heed, respect, [See PERCEIVE].

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KEY: Obsolete.

SYN: Antiquated, past, effete, disused, archaic, old-fashioned.

ANT: Fashionable, modern, current, customary, operative, extant.