Perhaps the word you are thinking of is circumspect.
OED sense 2a, defines the adjective circumspect (noun: circumspection) as:
. Of persons: Watchful on all sides, attentive to everything,
cautious, heedful of all circumstances that may affect action or
It derives from the French circonspect (Latin - circumspectus)
1430 Lydgate tr. Hist. Troy ii. xvi, Circumspect in all his
a1513 R. Fabyan New Cronycles Eng. & Fraunce (1516) I. ccxlvi. f.
clxviii, Which in all his faytes is so circumspecte.
1542 A. Borde Compend. Regyment Helth xxiii. sig. L.iv, Sanguyne
men..must be cyrcumspect in eatynge of theyr meate.
1597 Shakespeare Richard III iv. ii. 32 High reaching Buckingham
growes circumspect .
1624 J. Smith Gen. Hist. Virginia iv. 147 This will make us more
a1727 I. Newton Chronol. Anc. Kingdoms Amended (1728) ii. 260
Herodotus was circumspect and faithful in his narrations.
1847 W. H. Prescott Hist. Conquest Peru I. iii. iv. 382 The wild
passes..practicable..for the sure and circumspect mule.
1881 W. Besant & J. Rice Chaplain of Fleet I. iii. 38, I was to be
circumspect in my behaviour.