Online

[on-lahyn, awn-] /ˈɒnˈlaɪn, ˈɔn-/

adjective
1.
operating under the direct control of, or connected to, a main computer.
2.
connected by computer to one or more other computers or networks, as through a commercial electronic information service or the Internet.
3.
of or denoting a business that transmits electronic information over telecommunications lines:
an online bookstore.
4.
available or operating on a computer or computer network:
an online dictionary.
5.
by means of or using a computer:
online shopping.
6.
Radio. (of a network) supplying affiliated stations with all or a substantial part of their programming.
7.
Television. of or relating to the final editing of a videotaped program.
8.
done or accomplished while in operation or active service:
online maintenance.
9.
located on major routes or rail lines:
online industries.
adverb
10.
with or through a computer, especially over a network.
/ˈɒnˌlaɪn/
adjective
1.
of, relating to, or concerned with a peripheral device that is directly connected to and controlled by the central processing unit of a computer
2.
of or relating to the internet: online shopping
3.
occurring as part of, or involving, a continuous sequence of operations, such as a production line
adverb
4.
while connected to a computer or the internet
adj.

in reference to computers, “directly connected to a peripheral device,” 1950 (originally as on-line).
online
(ŏn’līn’)
Connected to or accessible by means of a computer or computer network.

A term referring to locations on or use of the Internet. The term can be used to refer to a specific location or Web page (“Our sales catalogues can be found online at — ”) or to a personal activity (“I went online to find the information you wanted.”)