Synset

serving as an essential component
<adj.all>   freq. cnt.: 32 freq. cnt.: 11 freq. cnt.: 10 freq. cnt.: 8 freq. cnt.: 3

cardinal

central

fundamental

key

primal

sample sentences

"a cardinal rule"
"the central cause of the problem"
"an example that was fundamental to the argument"
"computers are fundamental to modern industrial structure"