Words to Describe impediment

How impediment often is described ("________ impediment")

• insuperable
• occult
• principal
• single
• biggest
• greater
• worst
• chief
• substantial
• loose
• obvious
• definite
• apparent
• crucial
• legal
• unforeseen
• temporary
• great
• only
• less
• potential
• real
• primary
• lawful
• physical
• natural
• additional
• permanent
• huge
• important
• formidable
• main
• minor
• serious
• artificial
• grave
• mechanical
• constant
• further
• grand
• sole
• unexpected
• key
• considerable
• slightest
• dangerous
• slight
• psychological
• insurmountable
• greatest
• constitutional
• least
• fatal
• possible
• structural
• powerful
• fundamental
• unnecessary
• absolute
• significant
• severe
• largest
• major
• canonical
• external