From WordNet (r) 3.0 (2006) [wn]:
strictly
adv 1: restricted to something; "we talked strictly business"
[syn: strictly, purely]
2: in a stringent manner; "the laws are stringently enforced";
"stringently controlled" [syn: strictly, stringently]
3: in a rigorous manner; "he had been trained rigorously by the
monks" [syn: rigorously, strictly]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Strictly \Strict"ly\, adv.
In a strict manner; closely; precisely.
[1913 Webster]