Standard kanji form. The second kanji 獪 is not a jōyō kanji, so the word may sometimes be written in kana.
ろうかいUsage3%
Kana spelling used when the kanji 獪 is avoided or unknown.
老かいUsage2%
search-only kanji form
Search-only mixed kanji-kana form; not a standard written form.
Etymology
Composed of 老 (old age) and 獪 (cunning, crafty). The exact historical derivation is uncertain, but the combination directly suggests 'cunning that comes with age'.