“Hic” or “hīc”?

Question

The pronoun hic (this) is written with short i in many places, e.g. Oxford Latin Dictionary. But in Lewis & Short: Latin-English dictionary and Allen and Greenough's New Latin Grammar, it is written as hīc with a long i.

Which is correct?

Answer 1

The vowel in the pronoun hic is certainly short, but in poetry the word often (not always!) scans as long even when it is followed by a vowel, as if it were actually hicc. This is not etymologically defensible, but it happens in analogy with the neuter nom./acc. sg. hо̆c (which L&S also has as hōc despite its short vowel), which is always hocc when followed by a vowel (in pronunciation and scansion if not in actual writing), because it reflects an older pronoun *hod + the deictic particle -c(e) (also seen in e.g. illic (ille + -c), tunc (tum + -c)), with assimilation of the d to the c.
The resulting geminate consonant disappears phonotactically when followed by a consonant or hiatus, which is presumably why it isn't written, but it's still lurking underneath. hic reflects *hĭ + the same particle and so doesn't genuinely/originally have the geminate, but it does show up.

L&S, like a lot of older works, uses macrons to indicate syllable weight, not vowel length. It's often the same thing, but not in this case.

(The adverb hīc does have a genuine long vowel, and so do some of the (other) declined forms of the pronoun.)