IPA: /ˌɛkstrəˈsɛljʊləli/
KK: /ɛkstrəˈsɛljələrli/
In a manner that occurs outside of cells.
The nutrients were absorbed extracellularly by the surrounding tissues.
Extracellularly → It is formed from "extra-" (meaning outside) and "cellular" (from Latin "cellula", meaning small room or cell) and the suffix "-ly" (meaning in a manner). The word "extracellularly" refers to something occurring in a manner that is outside of cells.
Think of 'extra' meaning 'outside' and 'cellular' referring to 'cells' — so 'extracellularly' means happening outside of cells.