A lot vs. Alot: 9 Grammatical Pitfalls
Latin, "alone" (see sole (adj.)), used in stage directions by 1590s. Masculine; the fem. is sola, but in stage directions solus typically serves for both. Also in phrases solus cum sola "alone with an unchaperoned woman" and solus cum solo "all on one's own," both literally meaning "alone with alone."