externally
adv.on the outside of something. You use this when talking about the outer surface of an object or when something happens outside of a group or company.
adv.relating to the outside or outer part of something; occurring outside a particular organization or system.
“The medicine should only be applied externally.”
“The company decided to hire an expert externally to get a fresh perspective on their marketing strategy.”
“While the building appears modern and well-maintained externally, the interior structural supports require significant renovation to meet current safety standards.”
Often used to contrast with 'internally'; typically follows the verb or the noun it modifies.
“I've used data from radio telescopes to suggest whether different parts of Orion KL are heated internally, as by a young, still-forming star, or externally, as by shock waves emanating from more evolved stars.”
From external + -ly.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.