I got myself in a controversial discussion on word classification. To my knowledge words can be classified as a) inherited from a parent language, b) inherited substrate words, c) a result of innovation and d) loan words.
For (a) we can consider the English word yard that comes from PIE *ghórdhos.
For (b) the English bard is an inherited word from a Celtic substrate.
For (c) the English word computer is an innovation.
For (d) the English paradise is actually Iranic.
Now from those 4 categories, which words can be actually considered English in a strict context? Obviously (a) and (c) can be definitely labelled English, (b) cannot but substrate words can occasionally be labelled with the inheritors name (e.g. we consider θάλασσα Greek word although it is a substrate word) and (d) cannot be labelled English.
So my questions are the following:
Is the statement above regarding the labeling correct?
Are there more word classifications?
Can a word that passes into the English vocabulary rightfully called 'English' in a strict sense?