covertly
adv. C1 Advanced US //koʊˈvɝtɫi// UK //kəʊvˈɜːtli// covert·ly
adv. in a secret or hidden way. You use this when someone does something without others knowing it is happening.
adv. in a secret or hidden manner; without being openly acknowledged or observed.
The two countries worked covertly to reach a peace agreement.
The spy moved through the city covertly, wearing a plain suit to avoid drawing attention to himself.
While the official policy remained unchanged, the government operated covertly to support the local resistance, fearing that public knowledge would provoke a military response.
From Middle English covertli, equivalent to covert + -ly.