A tactic or artifice designed to gain the upper hand, especially one involving underhanded dealings or deception. / Specifically, such a tactic or artifice in military operation.

plural of stratagem

of or pertaining to a stratum

(obsolete) strategic; involving stratagem

(law, US) A legal tactic in court proceedings, intended to place the opponent on to the wrong foot by unethical use of court procedures:

Of or relating to stratarchy.

plural of stratarchy

An organization having a number of different strata within which power and influence are distributed.

(obsolete) strategist

(obsolete) strategic