alone

modif.

1. Separate from others

   lone, lonely, solitary, separate, lonesome, deserted, forlorn, lorn, isolated, individual, forsaken, desolate, detached, companionless, friendless, unaccompanied, unescorted, abandoned, secluded, apart, by oneself, under one's own power, unassisted, unaided, single-handed, single, widowed, unmarried, unattached, solo, solus (Latin), in solitude, by one's lonesome*.

   Antonyms accompanied, attended, escorted.

2. Exclusive of others

   solely, singly, simply; see only 1.

3. Unique

   unparalleled, unexampled, unequaled; see unique 1.

alone, unqualified, denotes the simple fact of being by oneself or itself; solitary and the more poetic lone convey the same sense but suggest more strongly the lack of companionship or association a solitary tree in the meadow a lone wanderer; lonely conveys a heightened sense of solitude and gloom the lonely sentinel walks his post; lonesome suggests a longing or yearning for companionship, often for a particular person the child is lonesome for her mother

let alone

1. not to mention, not to speak of, also, in addition to; see besides.

2. ignore, leave to oneself, isolate, refrain from disturbing;

let well enough alone