1. In theory; according to the assumed facts 
2. In a theoretical manner
   "he worked the problem out theoretically"

See also: theoretical

Antonym: empirically

• unsealed
• unseamanlike
• unseamed
• unsearchable
• unseasonable
• unseasonableness
• unseasonably
• unseasoned
• unseat
• unseaworthy
• unsectarian
• unsecure
• unsecured
• unsecured bond
• unseductive
• unseeable
• unseeded
• unseeing
• unseeingly
• unseemliness
• unseemly
• unseen
• unsegmented
• unsegregated
• unselected