Common Words:
* inactive: not active
* incorrect: not correct
* incapable: not capable
* incomplete: not complete
* inconsistent: not consistent
* indecent: not decent
* inefficient: not efficient
* ineffective: not effective
* infrequent: not frequent
* insecure: not secure
* insincere: not sincere
* invisible: not visible
* invalid: not valid
Less Common Words:
* inadvisable: not advisable
* inapplicable: not applicable
* inattentive: not attentive
* incomprehensible: not comprehensible
* inconclusive: not conclusive
* indecisive: not decisive
* indefensible: not defensible
* inexplicable: not explicable
* infamous: not famous (in a bad way)
* inhuman: not human
* inscrutable: not scrutable (difficult to understand)
* intact: not touched (but can also mean whole or complete)
* intangible: not tangible (cannot be touched)
Important Notes:
* The prefix "in" can also mean "in" or "into" (e.g., "inside," "inhabit").
* Sometimes the prefix "in" means the opposite of what you might expect. For example, "invaluable" means "very valuable," not "not valuable."
Let me know if you'd like to explore more words with this prefix!